Alpha-cyanoacrylates

ABSTRACT

α-Cyanoacrylates of the formula I  
                 
where: 
         R 1  is OR a  wherein R a  is hydrogen, substituted alkyl, branched alkyl, branched alkenyl, cycloloalkyl, heterocyclyl, aryl, phenylalkyl or alkylimino; 
           is NR b R c  wherein R b  is hydrogen, alkyl which may be substituted, alkenyl, alkynyl; 
               R c  is hydrogen, alkyl which may be substituted alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, phenylalkyl or alkylimino;    or R b  and R c  form an alkandiyl-chain which may be substituted; or    
               is SR d  wherein R d  is hydrogen, alkyl which may be substituted, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, phenylalkyl or alkylimino;    
           R 2  is alkyl which may be substituted; is alkenyl or alkynyl;    R 3  is alkyl may be substituted; is alkenyl or alkynyl;    R 4  is hydrogen, halogen, cyano or alkyl; and their agriculturally useful salts, processes and intermediates for their preparation; and the use of these compounds or of compositions comprising these compounds for controlling undesirable plants are described.

The present invention relates to α-cyanoacrylates of the formula I

where:

-   -   R¹ is OR^(a) wherein R^(a) is hydrogen, C₁-C₆-alkyl which is         partially or fully halogenated and/or carries a substituent from         the group consisting of hydroxy, cyano, C₃-C₆-cycloalkyl, three-         to six-membered heterocyclyl, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio,         C₁-C₆-haloalkylthio, C₁-C₆-alkylsulfinyl,         C₁-C₆-haloalkylsulfinyl, C₁-C₆-alkylsulfonyl,         C₁-C₆-haloalkylsulfonyl, (C₁-C₄)alkoxycarbonyl, aminocarbonyl,         (C₁-C₆)alkylaminocarbonyl, di(C₁-C₆)alkylaminocarbonyl;         -   is branched C₃-C₆-alkyl, branched C₄-C₆-alkenyl,             C₃-C₆-alkynyl, C₃-C₆-cycloalkyl, four- to six-membered             heterocyclyl, aryl, phenyl(C₁-C₄)alkyl or (C₁-C₆)alkylimino;         -   is NR^(b)R^(c) wherein R^(b) is hydrogen, C₁-C₆-alkyl which             may be partially or fully halogenated and/or may carry a             substituent from the group consisting of hydroxy, cyano,             C₁-C₆-alkoxy, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio,             C₁-C₆-halogenalkylthio, C₁-C₆-alkylsulfinyl,             C₁-C₆-halogenalkylsulfinyl, C₁-C₆-alkylsulfonyl and             C₁-C₆-halogenalkylsulfonyl;             -   is C₂-C₆-alkenyl, C₂-C₆-alkynyl;             -   R^(c) is hydrogen, C₁-C₆-alkyl which may be partially or                 fully halogenated and/or may carry a substituent from                 the group consisting of hydroxy, cyano,                 C₃-C₆-cycloalkyl, three- to six-membered heterocyclyl,                 C₁-C₆-alkoxy, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio,                 C₁-C₆-haloalkylthio, C₁-C₆-alkylsulfinyl,                 C₁-C₆-haloalkylsulfinyl, C₁-C₆-alkylsulfonyl,                 C₁-C₆-haloalkylsulfonyl, (C₁-C₄)alkoxycarbonyl,                 aminocarbonyl, (C₁-C₆)alkylaminocarbonyl, di                 (C₁-C₆)alkylaminocarbonyl;             -   is C₃-C₆-alkenyl, C₃-C₆-alkynyl, C₃-C₆-cycloalkyl,                 four-to-six-membered heterocyclyl,aryl,                 phenyl(C₁-C₄-)alkyl or (C₁-C₆)alkylimino;             -   or R^(b) and R^(c) together from a 1,4-butanediyl-,                 1,5-pentanediyl- or 1,6-hexanediyl—chain, wherein each                 of the chains may carry one or more C₁-C₆-alkyl-groups;                 or         -   is SR^(d) wherein R^(d) has the some meaning as R^(c);     -   R² is C₁-C₆-alkyl which may be partially or fully halogenated         and/or may carry a substituent from the group consisting of         cyano, C₁-C₆-alkoxy, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio,         C₁-C₆-haloalkylthio, C₁-C₆-alkylsulfinyl,         C₁-C₆-haloalkylsulfinyl, C₁-C₆-alkylsulfonyl and         C₁-C₆-haloalkylsulfonyl;         -   is C₂-C₆-alkenyl or C₂-C₆-alkynyl;     -   R³ is C₂-C₆-alkyl or C₁-C₆-alkyl which is partially or fully         halogenated and/or carries a substituent from the group         consisting of cyano, C₁-C₆-alkoxy, C₁-C₆-haloalkoxy,         C₁-C₆-alkylthio, C₁l-C₆-haloalkylthio, C₁-C₆-alkylsulfinyl,         C₁-C₆-haloalkylsulfinyl, C₁-C₆-alkylsulfonyl and         C₁-C₆-haloalkylsulfonyl;         -   is C₂-C₆-alkenyl or C₂-C₆-alkynyl;     -   R⁴ is hydrogen, halogen, cyano or C₁-C₆-alkyl,         and their agriculturally useful salts.

Moreover, the invention relates to processes and intermediates for preparing compounds of formula I, to compositions comprising them and to the use of these derivatives or the compositions comprising them for controlling harmful plants.

α-Cyano-β-aminoalkylacrylic esters are known from the literature, for example from Hayashi et al., Bull. Chem. Soc. Jpn. 40, (1967), 2160-2163. JP 61109752 discloses α,β-unsaturated carboxylic acid derivatives as plant growth regulators. WO 98/00598 (=U.S. Pat. No. 4,902,334) discloses herbicidally active crotonic acid derivatives.

However, the herbicidal properties of the prior-art compounds and/or their compatibility with crop plants are not entirely satisfactory. It is therefore an object of the present invention to provide novel, in particular herbicidally active, compounds having improved properties.

We have found that this object is achieved by the α-cyanoacrylates of formula I and their herbicidal activity.

Furthermore, we have found herbicidal compositions which comprise the compounds I and have very good herbicidal activity. Moreover, we have found processes for preparing these compositions and methods for controlling undesirable vegetation using the compounds I.

The α-cyanoacrylates of formula I are always present as (Z) isomers, i.e. amino group and ester radical are on the same side of the double bond.

Depending on the substitution pattern, the compounds of formula I can contain one or more chiral centers, in which case they are present as enantiomers or mixtures of diastereomers. This invention provides both the pure enantiomers or diastereomers and mixtures thereof.

The compounds of formula I can also be present in the form of their agriculturally useful salts, where the type of salt is usually immaterial. In general, suitable salts are the salts of those cations or the acid addition salts of those acids whose cations and anions, respectively, do not adversely affect the herbicidal activity of the compounds I.

Suitable cations are, in particular, ions of the alkali metals, preferably lithium, sodium and potassium, of the alkaline earth metals, preferably calcium and magnesium, and of the transition metals, preferably manganese, copper, zinc and iron, and also ammonium, where here, if desired, one to four hydrogen atoms may be replaced by C₁-C₄-alkyl, hydroxy-C₁-C₄-alkyl, C₁-C₄-alkoxy-C₁-C₄-alkyl, hydroxy-C₁-C₄-alkoxy-C₁-C₄-alkyl, phenyl or benzyl, preferably ammonium, dimethylammonium, diisopropylammonium, tetramethylammonium, tetrabutylammonium, 2-(2-hydroxyeth-l-oxy)eth-1-ylammonium, di-(2-hydroxyeth-1-yl)ammonium, trimethylbenzylammonium, furthermore phosphonium ions, sulfonium ions, preferably tri(C₁-C₄-alkyl)sulfonium, and sulfoxonium ions, preferably tri (C₁-C₄-alkyl)sulfoxonium.

Anions of useful acid addition salts are primarily chloride, bromide, fluoride, hydrogen sulfate, sulfate, dihydrogen phosphate, hydrogen phosphate, nitrate, hydrogen carbonate, carbonate, hexafluorosilicate, hexafluorophosphate, benzoate, and also the anions of C₁-C₄-alkanoic acids, preferably formate, acetate, propionate and butyrate.

The organic moieties mentioned for the substituents R¹-R⁷ and R^(a)-R^(d) are collective terms for individual enumerations of the individual group members. All hydrocarbon chains, i.e. all alkyl, alkenyl, alkynyl, haloalkyl, cyanoalkyl, alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylsulfinyl, haloalkylsulfinyl, alkylsulfonyl and haloalkylsulfonyl moieties can be straight-chain or branched unless indicated otherwise. Unless indicated otherwise, halogenated substituents preferably carry one to five identical or different halogen atoms. The term halogen represents in each case fluorine, chlorine, bromine or iodine.

Examples of other meanings are:

-   -   C₁-C₄-alkyl as well as the alkyl parts of (C₁-C₄)-alkoxycarbonyl         and phenyl(C₁-C₄)alkyl: for example methyl, ethyl, propyl,         1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl and         1,1-dimethylethyl;     -   C₁-C₆-alkyl as well as the alkyl parts of (C₁-C₆)alkyl         aminocarbonyl, di(C₁-C₆)alkylaminocarbonyl and C₁-C₆-alkylimino:         C₁-C₄-alkyl as mentioned above, and also, for example, pentyl,         1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl,         1-ethylpropyl, hexyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl,         1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl,         1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl,         2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl,         1-ethylbutyl, 2-ethylbutyl, 1,1,2-trimethylpropyl,         1-ethyl-l-methylpropyl and 1-ethyl-3-methylpropyl;     -   branched C₃-C₆-alkyl: a branched saturated hydrocarbon having 3         to 6 carbon atoms, such as, for example, 1-methylethyl,         1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl,         1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl,         1-ethylpropyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl,         1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl,         1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl,         2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl,         1-ethylbutyl, 2-ethylbutyl, 1,1,2-trimethylpropyl,         1-ethyl-1-methylpropyl and 1-ethyl-3-methylpropyl;     -   C₃-C₆-cycloalkyl: a monocyclic saturated hydrocarbon having 3 to         6 ring members, such as cyclopropyl, cyclobutyl, cyclopentyl and         cyclohexyl,     -   four- to six-membered heterocyclyl: a monocyclic, saturated or         partial unsaturated cycle having four to six ring members, which         comprises apart from carbon atoms one to four nitrogen atoms, or         one or two oxygen atoms, or one or two sulfur atom, or one to         three nitrogen atoms and an oxygen atom, or one to three         nitrogen atoms and a sulfur atom, or one sulfur and one oxygen         atom, for example:         -   three- or four-membered heterocycles like 2-oxetanyl,             3-oxetanyl, 2-thiethanyl, 3-thiethanyl, 1-azetidinyl,             2-azetidinyl, 1-azetinyl, 2-azetinyl;         -   five membered saturated heterocycles like             2-tetrahydrofuranyl, 3-tetrahydrofuranyl,             2-tetrahydrothienyl, 3-tetrahydrothienyl,             1-pyrrolidinyl,2-pyrrolidinyl, 3-pyrrolidinyl,             3-isoxazolidinyl, 4-isoxazolidinyl, 5-isoxazolidinyl,             2-isothiazolidinyl, 3-isothiazolidinyl, 4-isothiazolidinyl,             5-isothiazolidinyl, 1-pyrazolidinyl, 3-pyrazolidinyl,             4-pyrazolidinyl, 5-pyrazolidinyl, 2-oxazolidinyl,             4-oxazolidinyl, 5-oxazolidinyl, 2-thiazolidinyl,             4-thiazolidinyl, 5-thiazolidinyl, 1-imidazolidinyl,             2-imidazolidinyl, 4-imidazolidinyl, 3-oxazolidinyl,             1,2,4-oxadiazolidin-3-yl, 1,2,4-oxadiazolidin-5-yl,             3-thiazolidinyl, 1,2,4-thiadiazolidin-3-yl,             1,2,4-thiadiazolidin-5-yl, 1,2,4-triazolidin-3-yl,             1,2,4-oxadiazolidin-2-yl, 1,2,4-oxadiazolidin-4-yl,             1,3,4-oxadiazolidin-2-yl, 1,2,4-thiadiazolidin-2-yl,             1,2,4-thiadiazolidin-4-yl, 1,3,4-thiadiazolidin-2-yl,             1,2,4-triazolidin-1-yl, 1,3,4-triazolidin-2-yl;         -   five membered partial unsaturated heterocycles like             2,3-dihydrofur-2-yl, 2,3-dihydrofur-3-yl,             2,4-dihydrofur-2-yl, 2,4-dihydrofur-3-yl, dioxolan-2-yl,             1,3-dioxol-2-yl, 2,3-dihydrothien-2-yl,             2,3-dihydrothien-3-yl, 2,4-dihydrothien-2-yl,             2,4-dihydrothien-3-yl, 4,5-dihydropyrrol-1-yl,             4,5-dihydropyrrol-2-yl, 4,5-dihydropyrrol-3-yl,             2,5-dihydropyrrol-1-yl, 2,5-dihydropyrrol-2-yl,             2,5-dihydropyrrol-3-yl, 2,3-dihydroisoxazol-1-yl,             2,3-dihydroisoxazol-3-yl, 2,3-dihydroisoxazol-4-yl,             2,3-dihydroisoxazol-5-yl, 2,5-dihydroisoxazol-3-yl,             2,5-dihydroisoxazol-4-yl, 2,5-dihydroisoxazol-5-yl,             4,5-dihydroisoxazol-2-yl, 4,5-dihydroisoxazol-3-yl,             4,5-dihydroisoxazol-4-yl, 4,5-dihydroisoxazol-5-yl,             2,3-dihydroisothiazol-1-yl, 2,3-dihydroisothiazol-3-yl,             2,3-dihydroisothiazol-4-yl, 2,3-dihydroisothiazol-5-yl,             2,5-dihydroisothiazol-3-yl, 2,5-dihydroisothiazol-4-yl,             2,5-dihydroisothiazol-5-yl, 4,5-dihydroisothiazol-1-yl,             4,5-dihydroisothiazol-3-yl, 4,5-dihydroisothiazol-4-yl,             4,5-dihydroisothiazol-5-yl, 2,3-dihydropyrazol-3-yl,             2,3-dihydropyrazol-2-yl, 2,3-dihydropyrazol-3-yl,             2,3-dihydropyrazol-4-yl, 2,3-dihydropyrazol-5-yl,             3,4-dihydropyrazol-4-yl, 3,4-dihydropyrazol-3-yl,             3,4-dihydropyrazol-4-yl, 3,4-dihydropyrazol-5-yl,             4,5-dihydropyrazol-4-yl, 4,5-dihydropyrazol-3-yl,             4,5-dihydropyrazol-4-yl, 4,5-dihydropyrazol-5-yl,             2,3-dihydroimidazol-1-yl, 2,3-dihydroimidazol-2-yl,             2,3-dihydroimidazol-3-yl, 2,3-dihydroimidazol-4-yl,             2,3-dihydroimidazol-5-yl, 4,5-dihydroimidazol -1-yl ,             4,5-dihydroimidazol-2-yl, 4,5-dihydroimidazol-4-yl,             4,5-dihydroimidazol-5-yl, 2,5-dihydroimidazol-1-yl,             2,5-dihydroimidazol-2-yl, 2,5-dihydroimidazol-4-yl,             2,5-dihydroimidazol-5-yl, 2,3-dihydrooxazol-2-yl,             2,3-dihydrooxazol-3-yl, 2,3-dihydrooxazol-4-yl,             2,3-dihydrooxazol-5-yl, 3,4-dihydrooxazol-2-yl,             3,4-dihydrooxazol-3-yl, 3,4-dihydrooxazol-4-yl,             3,4-dihydrooxazol-5-yl, 2,3-dihydrothiazol-2-yl,             2,3-dihydrothiazol-3-yl, 2,3-dihydrothiazol-4-yl,             2,3-dihydrothiazol-5-yl, 3,4-dihydrothiazol-2-yl,             3,4-dihydrothiazol-3-yl, 3,4-dihydrothiazol-4-yl,             3,4-dihydrothiazol-5-yl, 3,4-dihydrothiazol-2-yl,             3,4-dihydrothiazol-3-yl, 3,4-dihydrothiazol-4-yl;         -   six-membered saturated heterocycles like 1-piperidinyl,             2-piperidinyl, 3-piperidinyl, 4-piperidinyl,             1,3-dioxan-5-yl, 1,4-dioxanyl, 1,3-dithian-5-yl,             1,3-dithianyl, 1,3-oxathian-5-yl, 1,4-oxathianyl,             2-tetrahydropyranyl, 3-tetrahydopyranyl,             4-tetrahydropyranyl, 2-tetrahydrothiopyranyl,             3-tetrahydrothiopyranyl,4-tetrahydrothiopyranyl,             1-hexahydropyridazinyl, 3-hexahydropyridazinyl,             4-hexahydropyridazinyl, 1-hexahydropyrimidinyl,             2-hexahydropyrimidinyl, 4-hexahydropyrimidinyl,             5-hexahydropyrimidinyl, 1-piperazinyl, 2-piperazinyl,             1,3,5-hexahydrotriazin-1-yl, 1,3,5-hexahydrotriazin-2-yl,             1,2,4-hexahydrotriazin-1-yl, 1,2,4-hexahydrotriazin-3-yl,             tetrahydro-1,3-oxazin-1-yl, tetrahydro-1,3-oxazin-2-yl,             tetrahydro-1,3-oxazin-6-yl, 1-morpholinyl, 2-morpholinyl,             3-morpholinyl;         -   six-membered partial unsaturated heterocycles like             2H-pyran-2-yl, 2H-pyran-3-yl, 2H-pyran-4-yl, 2H-pyran-5-yl,             2H-pyran-6-yl, 2H-thiopyran-2-yl, 2H-thiopyran-3-yl,             2H-thiopyran-4-yl, 2H-thiopyran-5-yl, 2H-thiopyran-6-yl,             5,6-dihydro-4H-1,3-oxazin-2-yl.     -   three- to six-membered heterocyclyl: four- to six-membered         heterocyclyl as mentioned above and also a monocyclic, saturated         or partial unsaturated cycle having three ring members, which         comprises apart from carbon atoms one nitrogen atom, one oxygen         atom or one sulfur atom, for example 2-oxiranyl, 2-aziridinyl,         2-thiiranyl.     -   C₂-C₆-alkenyl: for example ethenyl, 1-propenyl, 2-propenyl,         1-methylethenyl, 1-butenyl, 2-butenyl, 3-butenyl,         1-methyl-1-propenyl, 2-methyl-1-propenyl, 1-methyl-2-propenyl,         2-methyl-2-propenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl,         4-pentenyl, 1-methyl-1-butenyl, 2-methyl-1-butenyl,         3-methyl-1-butenyl, 1-methyl-2-butenyl, 2-methyl-2-butenyl,         3-methyl-2-butenyl, 1-methyl-3-butenyl, 2-methyl-3-butenyl,         3-methyl-3-butenyl, 1,1-dimethyl-2-propenyl,         1,2-dimethyl-1-propenyl, 1,2-dimethyl-2-propenyl,         1-ethyl-1-propenyl, 1-ethyl-2-propenyl, 1-hexenyl, 2-hexenyl,         3-hexenyl, 4-hexenyl, 5-hexenyl, 1-methyl-1-pentenyl,         2-methyl-1-pentenyl, 3-methyl-1-pentenyl, 4-methyl-1-pentenyl,         1-methyl-2-pentenyl, 2-methyl-2-pentenyl, 3-methyl-2-pentenyl,         4-methyl-2-pentenyl, 1-methyl-3-pentenyl, 2-methyl-3-pentenyl,         3-methyl-3-pentenyl, 4-methyl-3-pentenyl, 1-methyl-4-pentenyl,         2-methyl-4-pentenyl, 3-methyl-4-pentenyl, 4-methyl-4-pentenyl,         1,1-dimethyl-2-butenyl, 1,1-dimethyl-3-butenyl,         1,2-dimethyl-1-butenyl, 1,2-dimethyl-2-butenyl,         1,2-dimethyl-3-butenyl, 1,3-dimethyl-1-butenyl,         1,3-dimethyl-2-butenyl, 1,3-dimethyl-3-butenyl,         2,2-dimethyl-3-butenyl, 2,3-dimethyl-1-butenyl,         2,3-dimethyl-2-butenyl, 2,3-dimethyl-3-butenyl,         3,3-dimethyl-1-butenyl, 3,3-dimethyl-2-butenyl,         1-ethyl-1-butenyl, 1-ethyl-2-butenyl, 1-ethyl-3-butenyl,         2-ethyl-1-butenyl, 2-ethyl-2-butenyl, 2-ethyl-3-butenyl,         1,1,2-trimethyl-2-propenyl, 1-ethyl-1-methyl-2-propenyl,         1-ethyl-2-methyl-1-propenyl and 1-ethyl-2-methyl-2-propenyl;     -   branched C₄-C₆-alkenyl: for example 1-methyl-1-propenyl,         2-methyl-1-propenyl, 1-methyl-2-propenyl, 2-methyl-2-propenyl,         1-methyl-1-butenyl, 2-methyl-1-butenyl, 3-methyl-1-butenyl,         1-methyl-2-butenyl, 2-methyl-2-butenyl, 3-methyl-2-butenyl,         1-methyl-3-butenyl, 2-methyl-3-butenyl, 3-methyl-3-butenyl,         1,1-dimethyl-2-propenyl, 1,2-dimethyl-1-propenyl,         1,2-dimethyl-2-propenyl, 1-ethyl-1propenyl, 1-ethyl-2-propenyl,         1-methyl-1-pentenyl, 2-methyl-1-pentenyl, 3-methyl-1-pentenyl,         4-methyl-1-pentenyl, 1-methyl-2-pentenyl, 2-methyl-2-pentenyl,         3-methyl-2-pentenyl, 4-methyl-2-pentenyl, 1-methyl-3-pentenyl,         2-methyl-3-pentenyl, 3-methyl-3-pentenyl, 4-methyl-3-pentenyl,         1-methyl-4-pentenyl, 2-methyl-4-pentenyl, 3-methyl-4-pentenyl,         4-methyl-4-pentenyl, 1,1-dimethyl-2-butenyl,         1,1-dimethyl-3-butenyl, 1,2-dimethyl-1-butenyl,         1,2-dimethyl-2-butenyl, 1,2-dimethyl-3-butenyl,         1,3-dimethyl-1-butenyl, 1,3-dimethyl-2-butenyl,         1,3-dimethyl-3-butenyl, 2,2-dimethyl-3-butenyl,         2,3-dimethyl-1-butenyl, 2,3-dimethyl-2-butenyl,         2,3-dimethyl-3-butenyl, 3,3-dimethyl-1-butenyl,         3,3-dimethyl-2-butenyl, 1-ethyl-1-butenyl, 1-ethyl-2-butenyl,         1-ethyl-3-butenyl, 2-ethyl-1-butenyl, 2-ethyl-2-butenyl,         2-ethyl-3-butenyl, 1,1,2-trimethyl-2-propenyl,         1-ethyl-1-methyl-2-propenyl, 1-ethyl-2-methyl-1-propenyl and         1-ethyl-2-methyl-2-propenyl;     -   C₃-C₆-alkynyl: for example 1-propynyl, 2-propynyl, 1-butynyl,         2-butynyl, 3-butynyl, 1-methyl-2-propynyl, 1-pentynyl,         2-pentynyl, 3-pentynyl, 4-pentynyl, 1-methyl-2-butynyl,         1-methyl-3-butynyl, 2-methyl-3-butynyl, 3-methyl-1-butynyl,         1,1-dimethyl-2-propynyl, 1-ethyl-2-propynyl, 1-hexynyl,         2-hexynyl, 3-hexynyl, 4-hexynyl, 5-hexynyl, 1-methyl-2-pentynyl,         1-methyl-3-pentynyl, 1-methyl-4-pentynyl, 2-methyl-3-pentynyl,         2-methyl-4-pentynyl, 3-methyl-1-pentynyl, 3-methyl-4-pentynyl,         4-methyl-1-pentynyl, 4-methyl-2-pentynyl,         1,1-dimethyl-2-butynyl, 1,1-dimethyl-3-butynyl,         1,2-dimethyl-3-butynyl, 2,2-dimethyl-3-butynyl,         3,3-dimethyl-1-butynyl, 1-ethyl-2-butynyl, 1-ethyl-3-butynyl,         2-ethyl-3-butynyl and 1-ethyl-1-methyl-2-propynyl;     -   C₂-C₆-alkynyl: C₃-C₆-alkynyl as mentioned above, and also         ethynyl;     -   C₁-C₆-alkoxy: for example methoxy, ethoxy, propoxy,         1-methylethoxy, butoxy, 1-methylpropoxy, 2-methylpropoxy,         1,1-dimethylethoxy, pentoxy, 1-methylbutoxy, 2-methylbutoxy,         3-methoxylbutoxy, 1,1-dimethylpropoxy, 1,2-dimethylpropoxy,         2,2-dimethylpropoxy, 1-ethylpropoxy, hexoxy, 1-methylpentoxy,         2-methylpentoxy, 3-methylpentoxy, 4-methylpentoxy,         1,1-dimethylbutoxy,1,2-dimethylbutoxy, 1,3-dimethylbutoxy,         2,2-dimethylbutoxy, 2,3-dimethylbutoxy, 3,3-dimethylbutoxy,         1-ethylbutoxy, 2-ethylbutoxy, 1,1,2-trimethylpropoxy,         1,2,2-trimethylpropoxy, l-ethyl-1-methylpropoxy and         l-ethyl-2-methylpropoxy;     -   C₁-C₆-haloalkoxy: a C₁-C₆-alkoxy radical as mentioned above         which is partially or fully substituted by fluorine, chlorine,         bromine and/or iodine, i.e., for example, fluoromethoxy,         difluoromethoxy, trifluoromethoxy, chlorodifluoromethoxy,         bromodifluoromethoxy, 2-fluoroethoxy, 2-chloroethoxy,         2-bromomethoxy, 2-iodoethoxy, 2,2-difluoroethoxy,         2,2,2-trifluoroethoxy, 2-chloro-2-fluoroethoxy,         2-chloro-2,2-difluoroethoxy, 2,2-dichloro-2-fluoroethoxy,         2,2,2-trichloroethoxy, pentafluoroethoxy, 2-fluoropropoxy,         3-fluoropropoxy, 2-chloropropoxy, 3-chloropropoxy,         2-bromopropoxy, 3-bromopropoxy, 2,2-difluoropropoxy,         2,3-difluoropropoxy, 2,3-dichloropropoxy,         3,3,3-trifluoropropoxy, 3,3,3-trichloropropoxy,         2,2,3,3,3-pentafluoropropoxy, heptafluoropropoxy,         1-(fluoromethyl)-2-fluoroethoxy,         1-(chloromethyl)-2-chloroethoxy, 1-(bromomethyl)-2-bromoethoxy,         4-fluorobutoxy, 4-chlorobutoxy, 4-bromobutoxy, nonafluorobutoxy,         5-fluoropentoxy, 5-chloropentoxy, 5-bromopentoxy, 5-iodopentoxy,         undecafluoropentoxy, 6-fluorohexoxy, 6-chlorohexoxy,         6-bromohexoxy, 6-iodohexoxy and dodecafluorohexoxy;     -   C₁-C₆-alkylthio: for example methylthio, ethylthio, propylthio,         1-methylethylthio, butylthio, 1-methylpropylthio,         2-methylpropylthio, 1,1-dimethylethylthio, pentylthio,         1-methylbutylthio, 2-methylbutylthio, 3-methylbutylthio,         2,2-dimethylpropylthio, 1-ethylpropylthio, hexylthio,         1,1-dimethylpropylthio, 1,2-dimethylpropylthio,         1-methylpentylthio, 2-methylpentylthio, 3-methylpentylthio,         4-methylpentylthio, 1,1-dimethylbutylthio,         1,2-dimethylbutylthio, 1,3-dimethylbutylthio,         2,2-dimethylbutylthio, 2,3-dimethylbutylthio,         3,3-dimethylbutylthio, 1-ethylbutylthio, 2-ethylbutylthio,         1,1,2-trimethylpropylthio, 1,2,2-trimethylpropylthio,         1-ethyl-1-methylpropylthio and 1-ethyl-2-methylpropylthio;     -   C₁-C₆-haloalkylthio: a C₁-C₆-alkylthio radical as mentioned         above which is partially or fully substituted by fluorine,         chlorine, bromine and/or iodine, i.e., for example,         fluoromethylthio, difluoromethylthio, trifluoromethylthio,         chlorodifluoromethylthio, bromodifluoromethylthio,         2-fluoroethylthio, 2-chloroethylthio, 2-bromoethylthio,         2-iodoethylthio, 2,2-difluoroethylthio,         2,2,2-trifluoroethylthio, 2,2,2-trichloroethylthio,         2-chloro-2-fluoroethylthio, 2-chloro-2,2-difluoroethylthio,         2,2-dichloro-2-fluoroethylthio, pentafluoroethylthio,         2-fluoropropylthio, 3-fluoropropylthio, 2-chloropropylthio,         3-chloropropylthio, 2-bromopropylthio, 3-bromopropylthio,         2,2-difluoropropylthio, 2,3-difluoropropylthio,         2,3-dichloropropylthio, 3,3,3-trifluoropropylthio,         3,3,3-trichloropropylthio, 2,2,3,3,3-pentafluoropropylthio,         heptafluoropropylthio, 1-(fluoromethyl)-2-fluoroethylthio,         1-(chloromethyl)-2-chloroethylthio,         1-(bromomethyl)-2-bromoethylthio, 4-fluorobutylthio,         4-chlorobutylthio, 4-bromobutylthio, nonafluorobutylthio,         5-fluoropentylthio, 5-chloropentylthio, 5-bromopentylthio,         5-iodopentylthio, undecafluoropentylthio, 6-fluorohexylthio,         6-chlorohexylthio, 6-bromohexylthio, 6-iodohexylthio and         dodecafluorohexylthio;     -   C₁-C₆-alkylsulfinyl (C₁-C₆-alkyl-S(═O)—): for example         methylsulfinyl, ethylsulfinyl, propylsulfinyl,         1-methylethylsulfinyl, butylsulfinyl, 1-methylpropylsulfinyl,         2-methylpropylsulfinyl, 1,1-dimethylethylsulfinyl,         pentylsulfinyl, 1-methylbutylsulfinyl, 2-methylbutylsulfinyl,         3-methylbutylsulfinyl, 2,2-dimethylpropylsulfinyl,         1-ethylpropylsulfinyl, 1,1-dimethylpropylsulfinyl,         1,2-dimethylpropylsulfinyl, hexylsulfinyl,         1-methylpentylsulfinyl, 2-methylpentylsulfinyl,         3-methylpentylsulfinyl, 4-methylpentylsulfinyl,         1,1-dimethylbutylsulfinyl, 1,2-dimethylbutylsulfinyl,         1,3-dimethylbutylsulfinyl, 2,2-dimethylbutylsulfinyl,         2,3-Dimethylbutylsulfinyl, 3,3-dimethylbutylsulfinyl,         1-ethylbutylsulfinyl, 2-ethylbutylsulfinyl,         1,1,2-trimethylpropylsulfinyl, 1,2,2-trimethylpropylsulfinyl,         1-ethyl-1-methylpropylsulfinyl and         1-ethyl-2-methylpropylsulfinyl;     -   C₁-C₆-haloalkylsulfinyl: a C₁-C₆-alkylsulfinyl radical as         mentioned above which is partially or fully substituted by         fluorine, chlorine, bromine and/or iodine, i.e., for example,         fluoromethylsulfinyl, difluoromethylsulfinyl,         trifluoromethylsulfinyl, chlorodifluoromethylsulfinyl,         bromodifluoromethylsulfinyl, 2-fluoroethylsulfinyl,         2-chloroethylsulfinyl, 2-bromoethylsulfinyl,         2-iodoethylsulfinyl, 2,2-difluoroethylsulfinyl,         2,2,2-trifluoroethylsulfinyl, 2,2,2-trichloroethylsulfinyl,         2-chloro-2-fluoroethylsulfinyl,         2-chloro-2,2-difluoroethylsulfinyl,         2,2-dichloro-2-fluoroethylsulfinyl, pentafluoroethylsulfinyl,         2-fluoropropylsulfinyl, 3-fluoropropylsulfinyl,         2-chloropropylsulfinyl, 3-chloropropylsulfinyl,         2-bromopropylsulfinyl, 3-bromopropylsulfinyl,         2,2-difluoropropylsulfinyl, 2,3-difluoropropylsulfinyl,         2,3-dichloropropylsulfinyl, 3,3,3-trifluoropropylsulfinyl,         3,3,3-trichloropropylsulfinyl,         2,2,3,3,3-pentafluoropropylsulfinyl, heptafluoropropylsulfinyl,         1-(fluoromethyl)-2-fluoroethylsulfinyl,         1-(chloromethyl)-2-chloroethylsulfinyl,         1-(bromomethyl)-2-bromoethylsulfinyl, 4-fluorobutylsulfinyl,         4-chlorobutylsulfinyl, 4-bromobutylsulfinyl,         nonafluorobutylsulfinyl, 5-fluoropentylsulfinyl,         5-chloropentylsulfinyl, 5-bromopentylsulfinyl,         5-iodopentylsulfinyl, undecafluoropentylsulfinyl,         6-fluorohexylsulfinyl, 6-chlorohexylsulfinyl,         6-bromohexylsulfinyl, 6-iodohexylsulfinyl and         dodecafluorohexylsulfinyl;     -   C₁-C₆-alkylsulfonyl (C₁-C₆-alkyl-S(═O)₂—): for example         methylsulfonyl, ethylsulfonyl, propylsulfonyl,         1-methylethylsulfonyl, butylsulfonyl, 1-methylpropylsulfonyl,         2-methylpropylsulfonyl, 1,1-dimethylethylsulfonyl,         pentylsulfonyl, 1-methylbutylsulfonyl, 2-methylbutylsulfonyl,         3-methylbutylsulfonyl, 1,1-dimethylpropylsulfonyl,         1,2-dimethylpropylsulfonyl, 2,2-dimethylpropylsulfonyl,         1-ethylpropylsulfonyl, hexylsulfonyl, 1-methylpentylsulfonyl,         2-methylpentylsulfonyl, 3-methylpentylsulfonyl,         4-methylpentylsulfonyl, 1,1-dimethylbutylsulfonyl,         1,2-dimethylbutylsulfonyl, 1,3-dimethylbutylsulfonyl,         2,2-dimethylbutylsulfonyl, 2,3-dimethylbutylsulfonyl,         3,3-dimethylbutylsulfonyl, 1-ethylbutylsulfonyl,         2-ethylbutylsulfonyl, 1,1,2-trimethylpropylsulfonyl,         1,2,2-trimethylpropylsulfonyl, 1-ethyl-1-methylpropylsulfonyl         and 1-ethyl-2-methylpropylsulfonyl;     -   C₁-C₆-haloalkylsulfonyl: a C₁-C₆-alkylsulfonyl radical as         mentioned above which is partially or fully substituted by         fluorine, chlorine, bromine and/or iodine, i.e., for example,         fluoromethylsulfonyl, difluoromethylsulfonyl,         trifluoromethylsulfonyl, chlorodifluoromethylsulfonyl,         bromodifluoromethylsulfonyl, 2-fluoroethylsulfonyl,         2-chloroethylsulfonyl, 2-bromoethylsulfonyl,         2-iodoethylsulfonyl, 2,2-difluoroethylsulfonyl,         2,2,2-trifluoroethylsulfonyl, 2-chloro-2-fluoroethylsulfonyl,         2-chloro-2,2-difluoroethylsulfonyl,         2,2-dichloro-2-fluoroethylsulfonyl,         2,2,2-trichloroethylsulfonyl, pentafluoroethylsulfonyl,         2-fluoropropylsulfonyl, 3-fluoropropylsulfonyl,         2-chloropropylsulfonyl, 3-chloropropylsulfonyl,         2-bromopropylsulfonyl, 3-bromopropylsulfonyl,         2,2-difluoropropylsulfonyl, 2,3-difluoropropylsulfonyl,         2,3-dichloropropylsulfonyl, 3,3,3-trifluoropropylsulfonyl,         3,3,3-trichloropropylsulfonyl,         2,2,3,3,3-pentafluoropropylsulfonyl, heptafluoropropylsulfonyl,         1-(fluoromethyl)-2-fluoroethylsulfonyl,         1-(chloromethyl)-2-chloroethylsulfonyl,         1-(bromomethyl)-2-bromoethylsulfonyl, 4-fluorobutylsulfonyl,         4-chlorobutylsulfonyl, 4-bromobutylsulfonyl,         nonafluorobutylsulfonyl, 5-fluoropentylsulfonyl,         5-chloropentylsulfonyl, 5-bromopentylsulfonyl,         5-iodopentylsulfonyl, 6-fluorohexylsulfonyl,         6-bromohexylsulfonyl, 6-iodohexylsulfonyl and         dodecafluorohexylsulfonyl.     -   Phenyl which may be annulated with one or two more phenyl rings,         for example phenyl, naphthyl and anthracenyl.

In a particular embodiment, the variables of the compounds of formula I have the following meanings, which meanings are, both on their own and in combination with one another, particular embodiments of the compounds of formula I:

Preference is given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a).

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R^(a) is C₁-C₂-alkyl which is partially or fully halogenated         and/or carries a substituent from the group consisting of cyano,         C₃-C₆-cycloalkyl, three- to six-membered heterocyclyl,         C₁-C₆-haloalkoxy, C₁-C₆-alkylthio, C₁-C₆-haloalkylthio,         C₁-C₆-alkylsulfinyl, C₁-C₆-halogenalkylsulfinyl,         C₁-C₆-alkylsulfonyl and C₁-C₆-halogenalkylsulfonyl;         -   is branched C₃-C₆-alkyl, branched C₄-C₆-alkenyl,             C₃-C₆-alkynyl, C₃-C₆-cycloalkyl or four- to six-membered             heterocyclyl.

Preference is given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R^(a) is branched C₃-C₆-alkyl;         -   particluarly preferably branched C₃-C₄-alkyl;         -   with particular preference 1-methylethyl, 2-methylpropyl or             1,1-dimethylethyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R^(a) is C₁-C₆-alkyl which is partially or fully halogenated         and/or carries a substituent from the group consisting of         cyclopropyl, C₂-C₆-alkenyl and C₂-C₆-alkynyl;         -   particularly preferably branched C₁-C₄-alkyl which is             partially or fully halogenated;         -   with particular preference ethyl or n-propyl which is             partially or fully halogenated.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R^(a) is C₃-C₆-cycloalkyl or four- to six-membered heterocyclyl;         -   particularly preferably C₃-C₅-cycloalkyl or four- to             six-membered heterocyclyl;         -   with particular preference cyclopropyl, cyclopentyl or             3-oxetanyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R² is C₁-C₆-alkyl which may be partially or fully halogenated         and/or may carry a substituent from the group consisting of         C₁-C₆-alkoxy;         -   particularly preferably C₁-C₄-alkyl;         -   with particular preference methyl or ethyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R² is C₁-C₆-alkyl;         -   with particular preference ethyl or n-propyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R³ is C₁-C₆-alkyl;         -   particularly preferably C₁-C₄-alkyl;         -   with particular preference ethyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R³ is C₁-C₆-alkyl which is partially or fully halogenated and/or         carries a substituent from the group consisting of C₁-C₆-alkoxy;         -   particularly preferably C₁-C₄-alkyl which is partially or             fully halogenated and/or carries a substituent from the             group consisting of C₁-C₆-alkoxy;         -   with particular preference methyl or ethyl which is             partially or fully halogenated and/or carries a substituent             from the group consisting of C₁-C₆-alkoxy.

Preference is furthermore given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R⁴ is hydrogen, fluorine, chlorine or C₁-C₄-alkyl;         -   particularly preferably hydrogen, fluorine or chlorine;         -   with particular preference hydrogen.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a) and

-   -   R² is C₁-C₆-alkyl;         -   with particular preference ethyl; and     -   R³ is C₂-C₆-alkenyl or C₂-C₆-alkynyl, with particular preference         2-propen-1-yl or 2-propyn-1-yl.

Particular preference is given to the α-cyanoacrylates of formula I wherein R¹ is OR^(a),

-   -   R^(a) is branched C₃-C₆-alkyl;         -   particularly preferably 1-methylethyl, 2-methylpropyl or             1,1-dimethylethyl;     -   R² is C₁-C₄-alkyl;         -   particularly preferably methyl, ethyl or n-propyl;         -   especially preferably methyl or ethyl;         -   also especially preferably ethyl or n-propyl;     -   R³ is C₂-C₄-alkyl;         -   particularly preferably ethyl or n-propyl, especially             preferably ethyl; and     -   R⁴ is hydrogen, fluorine or chlorine;         -   particularly preferably hydrogen.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c).

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R^(c) is C₃-C₆-alkenyl or C₃-C₆-alkynyl;         -   preferably C₃-C₄-alkenyl or C₃-C₄-alkynyl;         -   particular preferably 1-methyl-2-propen-1-yl,             1,1-dimethyl-2-propen-1-yl; 2-propyn-1-yl or             1-methyl-2-propyn-1-yl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl:         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R^(c) is C₃-C₆-cycloalkyl or three- to six-membered         heterocyclyl;         -   preferably C₃-C₅-cycloalkyl or four- to six-memberd             heterocyclyl;         -   particular preferably cyclopropyl, cyclopentyl, 3-oxetanyl,             3-tetrahydrofuranyl or 4-tetrahydropyranyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R² is C₁-C₆-alkyl, which may be partially or fully halogenated         and/or may carry a substituent from the group consisting of         C₁-C₆-alkoxy;         -   preferably C₁-C₄-alkyl;         -   particular preferably methyl, ethyl or n-propyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R² and R³ are inderpendently of each other C₂-C₆-alkyl,         preferably C₂-C₄-alkyl, particular preferably ethyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R³ is C₂-C₆-alkenyl or C₂-C₆-alkynyl;         -   preferably C₂-C₄-alkenyl or C₂-C₄-alkynyl;         -   particular preferably 2-propen-1-yl or 2-propyn-1-yl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R⁴ is hydrogen, fluorine, chlorine or C₁-C₄-alkyl;         -   preferably hydrogen, fluorine or chlorine;         -   particular preferably hydrogen.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl.     -   R² is C₂-C₄-alkyl;         -   preferably ethyl; and     -   R³ is C₂-C₆-alkenyl or C₂-C₆-alkynyl;         -   preferably 2-propen-1-yl or 2-propyn-1-yl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is NR^(b)R^(c), where

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;     -   R² is C₁-C₄-alkyl;         -   preferably methyl, ethyl, or n-propyl;     -   R³ is C₂-C₄-alkyl;         -   preferably ethyl or n-propyl; and     -   R⁴ is hydrogen.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d).

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   R^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   R^(d) is C₃-C₆-alkenyl or C₃-C₆-alkynyl;         -   preferably C₃-C₄-alkenyl or C₃-C₄-alkynyl;         -   particular preferably 1-methyl-2-propen-1-yl,             1,1-dimethyl-2-propen-1-yl;2-propyn-1-yl or             1-methyl-2-propyn-1-yl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   R^(d) is C₃-C₆-alkenyl or three-to six-memberd heterocyclyl;         -   preferably C₃-C₅-cycloalkyl or four-to-six-memberd             heterocyclyl;         -   particular preferably cyclopropyl, cyclopentyl, 3-oxetanyl,             3-tetrahydrofuranyl or 4-tetrahydropyranyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   R^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R² is C₁-C₆-alkyl which may be partially or fully halogenated         and/or may carry a substituent from the group consisting of         C₁-C₆-alkoxy;         -   preferably C₁-C₄-alkyl;         -   particular preferably methyl, ethyl or n-propyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   R^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R² and R³ are independently of each other C₂-C₆-alkyl;         -   preferably C₂-C₄-alkyl;         -   particular preferably ethyl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   R^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R³ is C₂-C₆-alkenyl or C₂-C₆-alkynyl;         -   preferably C₂-C₄-alkenyl or C₂-C₆-alkynyl;         -   particular preferably 2-propen-1-yl or 2-propyn-1-yl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   SR^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R⁴ is hydrogen, fluorine, chlorine or C₁-C₄-alkyl;         -   preferably hydrogen, fluorine or chlorine;         -   particular preferably hydrogen.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   SR^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R² is C₂-C₄-alkyl;         -   preferably ethyl; and     -   R³ is C₂-C₆-alkenyl or C₂-C₆-alkenyl;         -   preferably 2-propen-1-yl or 2-propyn-1-yl.

Preference is also given to the α-cyanoacrylates of formula I wherein R¹ is SR^(d), where

-   -   R^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;             and     -   R² is C₁-C₄-alkyl;         -   preferably methyl, ethyl, or n-propyl;     -   R³ is C₂-C₄-alkyl;         -   preferably ethyl, or n-propyl; and     -   R⁴ is hydrogen.

Extraordinary preference is given to the compounds of formula I.1 (corresponds to formula I where R¹ is OR^(a) wherein R^(a) is i-C₃H₇ and R⁴ is H), in particular to the compounds of formulae I.1.1 to I.1.79 of table 1, where the definitions of the variables R¹ to R⁴ are of particular importance for the compounds according to the invention not only in combination with one another, but in each case also on their own. TABLE 1 I.1

No. R² R³ I.1.1 CH₃ CH₃ I.1.2 CH₃ C₂H₅ I.1.3 CH₃ nC₃H₇ I.1.4 CH₃ iC₃H₇ I.1.5 CH₃ nC₄H₉ I.1.6 CH₃ CH₂CH(CH₃)₂ I.1.7 CH₃ CH(CH₃)C₂H₅ I.1.8 CH₃ tC₄H₉ I.1.9 C₂H₅ C₂H₅ I.1.10 C₂H₅ nC₃H₇ I.1.11 C₂H₅ iC₃H₇ I.1.12 C₂H₅ nC₄H₉ I.1.13 C₂H₅ CH₂CH(CH₃)₂ I.1.14 C₂H₅ CH(CH₃)C₂H₅ I.1.15 C₂H₅ tC₄H₉ I.1.16 nC₃H₇ nC₃H₇ I.1.17 nC₃H₇ iC₃H₇ I.1.18 iC₃H₇ iC₃H₇ I.1.19 CH₂F CH₃ I.1.20 CH₂F C₂H₅ I.1.21 CH₂F CH₂F I.1.22 CH₂Cl CH₃ I.1.23 CH₂Cl C₂H₅ I.1.24 CH₂Cl CH₂Cl I.1.25 CH₂Br CH₃ I.1.26 CH₂Br C₂H₅ I.1.27 CH₂Br CH₂Br I.1.28 CHF₂ CH₃ I.1.29 CHF₂ C₂H₅ I.1.30 CHF₂ CHF₂ I.1.31 CF₃ CH₃ I.1.32 CF₃ C₂H₅ I.1.33 CF₃ CF₃ I.1.34 (CH₂)₂F CH₃ I.1.35 (CH₂)₂F C₂H₅ I.1.36 (CH₂)₂F (CH₂)₂F I.1.37 (CH₂)₂Cl CH₃ I.1.38 (CH₂)₂Cl C₂H₅ I.1.39 (CH₂)₂Cl (CH₂)₂Cl I.1.40 (CH₂)₂Br CH₃ I.1.41 (CH₂)₂Br C₂H₅ I.1.42 (CH₂)₂Br (CH₂)₂Br I.1.43 CH₂CF₃ CH₃ I.1.44 CH₂CF₃ C₂H₅ I.1.45 CH₂CF₃ CH₂CF₃ I.1.46 CH₂OCH₃ CH₃ I.1.47 CH₂OCH₃ C₂H₅ I.1.48 CH₂OCH₃ CH₂OCH₃ I.1.49 (CH₂)₂OCH₃ CH₃ I.1.50 (CH₂)₂OCH₃ C₂H₅ I.1.51 (CH₂)₂OCH₃ (CH₂)₂OCH₃ I.1.52 (CH₂)₃OCH₃ CH₃ I.1.53 (CH₂)₃OCH₃ C₂H₅ I.1.54 (CH₂)₃OCH₃ (CH₂)₃OCH₃ I.1.55 CH(CH₃)CH₂OCH₃ CH₃ I.1.56 CH(CH₃)CH₂OCH₃ C₂H₅ I.1.57 CH(CH₃)CH₂OCH₃ CH(CH₃)CH₂OCH₃ I.1.58 CH₂CH(CH₃)OCH₃ CH₃ I.1.59 CH₂CH(CH₃)OCH₃ C₂H₅ I.1.60 CH₂CH(CH₃)OCH₃ CH₂CH(CH₃)OCH₃ I.1.61 CH₂OC₂H₅ CH₃ I.1.62 CH₂OC₂H₅ C₂H₅ I.1.63 CH₂OC₂H₅ CH₂OC₂H₅ I.1.64 (CH₂)₂OC₂H₅ CH₃ I.1.65 (CH₂)₂OC₂H₅ C₂H₅ I.1.66 (CH₂)₂OC₂H₅ (CH₂)₂OC₂H₅ I.1.67 (CH₂)₃OC₂H₅ CH₃ I.1.68 (CH₂)₃OC₂H₅ C₂H₅ I.1.69 (CH₂)₃OC₂H₅ (CH₂)₃OC₂H₅ I.1.70 CH(CH₃)CH₂OC₂H₅ CH₃ I.1.71 CH(CH₃)CH₂OC₂H₅ C₂H₅ I.1.72 CH(CH₃)CH₂OC₂H₅ CH(CH₃)CH₂OC₂H₅ I.1.73 CH₂CH(CH₃)OC₂H₅ CH₃ I.1.74 CH₂CH(CH₃)OC₂H₅ C₂H₅ I.1.75 CH₂CH(CH₃)OC₂H₅ CH₂CH(CH₃)OC₂H₅ I.1.76 CH₂CH═CH₂ C₂H₅ I.1.77 CH₂CH═CH₂ CH₂CH═CH₂ I.1.78 CH₂CH═CH₂ CH₂C═CH I.1.79 CH₂C≡CH CH₂C≡CH

Extraordinary preference is also given to the compounds of formula I.2, in particular to the compounds of formulae I.2.1 to I.2.79 which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CH(CH₃)₂.

Extraordinary preference is also given to the compounds of formula I.3, in particular to the compounds of formulae I.3.1 to I.3.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH(CH₃)C₂H₅.

Extraordinary preference is also given to the compounds of formula I.4, in particular to the compounds of formulae I.4.1 to I.4.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is tC₄H₉.

Extraordinary preference is also given to the compounds of formula I.5, in particular to the compounds of formulae I.5.1 to I.5.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH(CH₃)CH═CH₂.

Extraordinary preference is also given to the compounds of formula I.6, in particular to the compounds of formulae I.6.1 to I.6.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂C(CH₃)═CH₂.

Extraordinary preference is also given to the compounds of formula I.7, in particular to the compounds of formulae I.7.1 to I.7.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH(CH₃)CH═CHCH₃.

Extraordinary preference is also given to the compounds of formula I.8, in particular to the compounds of formulae I.8.1 to I.8.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CCH.

Extraordinary preference is also given to the compounds of formula I.9, in particular to the compounds of formulae I.9.1 to I.9.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CHCH₃CCH.

Extraordinary preference is also given to the compounds of formula I.10, in particular to the compounds of formulae I.10.1 to I.10.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CCCH₃.

Extraordinary preference is also given to the compounds of formula I.11, in particular to the compounds of formulae I.11.1 to I.11.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is (CH₂)₂CCH.

Extraordinary preference is also given to the compounds of formula I.12, in particular to the compounds of formulae I.12.1 to I.12.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CHF₂.

Extraordinary preference is also given to the compounds of formula I.13, in particular to the compounds of formulae I.13.1 to I.13.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CF₃.

Extraordinary preference is also given to the compounds of formula I.14, in particular to the compounds of formulae I.14.1 to I.14.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is (CH₂)₂CH₂F.

Extraordinary preference is also given to the compounds of formula I.15, in particular to the compounds of formulae I.15.1 to I.15.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is (CH₂)₂CF₃.

Extraordinary preference is also given to the compounds of formula I.16, in particular to the compounds of formulae I.16.1 to I.16.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CHCl₂.

Extraordinary preference is also given to the compounds of formula I.17, in particular to the compounds of formulae I.17.1 to I.17.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CCl₃.

Extraordinary preference is also given to the compounds of formula I.18, in particular to the compounds of formulae I.18.1 to I.18.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is (CH₂)₂CH₂Cl.

Extraordinary preference is also given to the compounds of formula I.19, in particular to the compounds of formulae I.19.1 to I.19.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is (CH₂)₂CCl₃.

Extraordinary preference is also given to the compounds of formula I.20, in particular to the compounds of formulae I.20.1 to I.20.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CHBr₂.

Extraordinary preference is also given to the compounds of formula I.21, in particular to the compounds of formulae I.21.1 to I.21.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH₂CBr₂.

Extraordinary preference is also given to the compounds of formula I.22, in particular to the compounds of formulae I.22.1 to I.22.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is (CH₂)₂CH₂Br.

Extraordinary preference is also given to the compounds of formula I.23, in particular to the compounds of formulae I.23.1 to I.23.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is (CH₂)₂CBr₃.

Extraordinary preference is also given to the compounds of formula I.24, in particular to the compounds of formulae I.24.1 to I.24.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is 3-oxetanyl.

Extraordinary preference is also given to the compounds of formula I.25, in particular to the compounds of formulae I.2₅.1 to I.2₅.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH(CH₃)CF₃.

Extraordinary preference is also given to the compounds of formula I.26, in particular to the compounds of formulae I.26.1 to I.26.79, which differ from the corresponding compounds of formulae I.1.1 to I.1.79 in that R^(a) is CH(CF₃)₂.

Extraordinary preference is also given to the compounds of formula I.27 (corresponds to formula I wherein R¹ is NR^(b)R^(c) with R^(c) is hydrogen and R⁴ is hydrogen), in particular to the compounds of formulae I.27.1 to I.27.180 of table 2, where the definitions of the variables R₁ to R₄ are of particular importance for the compounds according to the inventions not only in combination with one another, but each case on their own. TABLE 2 I.27

No. R^(b) R² R³ I.27.1 H C₂H₅ C₂H₅ I.27.2 H C₂H₅ nC₃H₇ I.27.3 H C₂H₅ iC₃H₇ I.27.4 H C₂H₅ nC₄H₉ I.27.5 H C₂H₅ CH₂CH(CH₃)₂ I.27.6 H C₂H₅ CH(CH₃)C₂C₅ I.27.7 H C₂H₅ CH₂CH═CH₂ I.27.8 H C₂H₅ CH₂C≡CH I.27.9 H nC₃H₇ nC₃H₇ I.27.10 H nC₃H₇ iC₃H₇ I.27.11 H nC₃H₇ nC₄H₉ I.27.12 H nC₃H₇ CH₂CH(CH₃)₂ I.27.13 H nC₃H₇ CH(CH₃)C₂C₅ I.27.14 H nC₃H₇ CH₂CH═CH₂ I.27.15 H nC₃H₇ CH₂C≡CH I.27.16 H iC₃H₇ iC₃H₇ I.27.17 H iC₃H₇ nC₄H₉ I.27.18 H iC₃H₇ CH₂CH(CH₃)₂ I.27.19 H iC₃H₇ CH(CH₃)C₂C₅ I.27.20 H iC₃H₇ CH₂CH═CH₂ I.27.21 H iC₃H₇ CH₂C≡CH I.27.22 H nC₄H₉ nC₄H₉ I.27.23 H nC₄H₉ CH₂CH(CH₃)₂ I.27.24 H nC₄H₉ CH(CH₃)C₂C₅ I.27.25 H nC₄H₉ CH₂CH═CH₂ I.27.26 H nC₄H₉ CH₂C≡CH I.27.27 H CH₂CH(CH₃)₂ CH₂CH(CH₃)₂ I.27.28 H CH₂CH(CH₃)₂ CH(CH₃)C₂C₅ I.27.29 H CH₂CH(CH₃)₂ CH₂CH═CH₂ I.27.30 H CH₂CH(CH₃)₂ CH₂C≡CH I.27.31 H CH(CH₃)C₂C₅ CH(CH₃)C₂C₅ I.27.32 H CH(CH₃)C₂C₅ CH₂CH═CH₂ I.27.33 H CH(CH₃)C₂C₅ CH₂C≡CH I.27.34 H CH₂CH═CH₂ CH₂CH═CH₂ I.27.35 H CH₂CH═CH₂ CH₂C≡CH I.27.36 H CH₂C≡CH CH₂C≡CH I.27.37 CH₃ C₂H₅ C₂H₅ I.27.38 CH₃ C₂H₅ nC₃H₇ I.27.39 CH₃ C₂H₅ iC₃H₇ I.27.40 CH₃ C₂H₅ nC₄H₉ I.27.41 CH₃ C₂H₅ CH₂CH(CH₃)₂ I.27.42 CH₃ C₂H₅ CH(CH₃)C₂C₅ I.27.43 CH₃ C₂H₅ CH₂CH═CH₂ I.27.44 CH₃ C₂H₅ CH₂C≡CH I.27.45 CH₃ nC₃H₇ nC₃H₇ I.27.46 CH₃ nC₃H₇ iC₃H₇ I.27.47 CH₃ nC₃H₇ nC₄H₉ I.27.48 CH₃ nC₃H₇ CH₂CH(CH₃)₂ I.27.49 CH₃ nC₃H₇ CH(CH₃)C₂C₅ I.27.50 CH₃ nC₃H₇ CH₂CH═CH₂ I.27.51 CH₃ nC₃H₇ CH₂C≡CH I.27.52 CH₃ iC₃H₇ iC₃H₇ I.27.53 CH₃ iC₃H₇ nC₄H₉ I.27.54 CH₃ iC₃H₇ CH₂CH(CH₃)₂ I.27.55 CH₃ iC₃H₇ CH(CH₃)C₂C₅ I.27.56 CH₃ iC₃H₇ CH₂CH═CH₂ I.27.57 CH₃ iC₃H₇ CH₂C≡CH I.27.58 CH₃ nC₄H₉ nC₄H₉ I.27.59 CH₃ nC₄H₉ CH₂CH(CH₃)₂ I.27.60 CH₃ nC₄H₉ CH(CH₃)C₂C₅ I.27.61 CH₃ nC₄H₉ CH₂CH═CH₂ I.27.62 CH₃ nC₄H₉ CH₂C≡CH I.27.63 CH₃ CH₂CH(CH₃)₂ CH₂CH(CH₃)₂ I.27.64 CH₃ CH₂CH(CH₃)₂ CH(CH₃)C₂C₅ I.27.65 CH₃ CH₂CH(CH₃)₂ CH₂CH═CH₂ I.27.66 CH₃ CH₂CH(CH₃)₂ CH₂C≡CH I.27.67 CH₃ CH(CH₃)C₂C₅ CH(CH₃)C₂C₅ I.27.68 CH₃ CH(CH₃)C₂C₅ CH₂CH═CH₂ I.27.69 CH₃ CH(CH₃)C₂C₅ CH₂C≡CH I.27.70 CH₃ CH₂CH═CH₂ CH₂CH═CH₂ I.27.71 CH₃ CH₂CN═CH₂ CH₂C≡CH I.27.72 CH₃ CH₂C≡CH CH₂C≡CH I.27.73 C₂H₅ C₂H₅ C₂H₅ I.27.74 C₂H₅ C₂H₅ nC₃H₇ I.27.75 C₂H₅ C₂H₅ iC₃H₇ I.27.76 C₂H₅ C₂H₅ nC₄H₉ I.27.77 C₂H₅ C₂H₅ CH₂CH(CH₃)₂ I.27.78 C₂H₅ C₂H₅ CH(CH₃)C₂C₅ I.27.79 C₂H₅ C₂H₅ CH₂CH═CH₂ I.27.80 C₂H₅ C₂H₅ CH₂C≡CH I.27.81 C₂H₅ nC₃H₇ nC₃H₇ I.27.82 C₂H₅ nC₃H₇ iC₃H₇ I.27.83 C₂H₅ nC₃H₇ nC₄H₉ I.27.84 C₂H₅ nC₃H₇ CH₂CH(CH₃)₂ I.27.85 C₂H₅ nC₃H₇ CH(CH₃)C₂C₅ I.27.86 C₂H₅ nC₃H₇ CH₂CH═CH₂ I.27.87 C₂H₅ nC₃H₇ CH₂C≡CH I.27.88 C₂H₅ iC₃H₇ iC₃H₇ I.27.89 C₂H₅ iC₃H₇ nC₄H₉ I.27.90 C₂H₅ iC₃H₇ CH₂CH(CH₃)₂ I.27.91 C₂H₅ iC₃H₇ CH(CH₃)C₂C₅ I.27.92 C₂H₅ iC₃H₇ CH₂CH═CH₂ I.27.93 C₂H₅ iC₃H₇ CH₂C≡CH I.27.94 C₂H₅ nC₄H₉ nC₄H₉ I.27.95 C₂H₅ nC₄H₉ CH₂CH(CH₃)₂ I.27.96 C₂H₅ nC₄H₉ CH(CH₃)C₂C₅ I.27.97 C₂H₅ nC₄H₉ CH₂CH═CH₂ I.27.98 C₂H₅ nC₄H₉ CH₂C≡CH I.27.99 C₂H₅ CH₂CH(CH₃)₂ CH₂CH(CH₃)₂ I.27.100 C₂H₅ CH₂CH(CH₃)₂ CH(CH₃)C₂C₅ I.27.101 C₂H₅ CH₂CH(CH₃)₂ CH₂CH═CH₂ I.27.102 C₂H₅ CH₂CH(CH₃)₂ CH₂C≡CH I.27.103 C₂H₅ CH(CH₃)C₂C₅ CH(CH₃)C₂C₅ I.27.104 C₂H₅ CH(CH₃)C₂C₅ CH₂CH═CH₂ I.27.105 C₂H₅ CH(CH₃)C₂C₅ CH₂C≡CH I.27.106 C₂H₅ CH₂CH═CH₂ CH₂CH═CH₂ I.27.107 C₂H₅ CH₂CH═CH₂ CH₂C≡CH I.27.108 C₂H₅ CH₂C≡CH CH₂C≡CH I.27.109 nC₃H₇ C₂H₅ C₂H₅ I.27.110 nC₃H₇ C₂H₅ nC₃H₇ I.27.111 nC₃H₇ C₂H₅ iC₃H₇ I.27.112 nC₃H₇ C₂H₅ nC₄H₉ I.27.113 nC₃H₇ C₂H₅ CH₂CH(CH₃)₂ I.27.114 nC₃H₇ C₂H₅ CH(CH₃)C₂C₅ I.27.115 nC₃H₇ C₂H₅ CH₂CH═CH₂ I.27.116 nC₃H₇ C₂H₅ CH₂C≡CH I.27.117 nC₃H₇ nC₃H₇ nC₃H₇ I.27.118 nC₃H₇ nC₃H₇ iC₃H₇ I.27.119 nC₃H₇ nC₃H₇ nC₄H₉ I.27.120 nC₃H₇ nC₃H₇ CH₂CH(CH₃)₂ I.27.121 nC₃H₇ nC₃H₇ CH(CH₃)C₂C₅ I.27.122 nC₃H₇ nC₃H₇ CH₂CH═CH₂ I.27.123 nC₃H₇ nC₃H₇ CH₂C≡CH I.27.124 nC₃H₇ iC₃H₇ iC₃H₇ I.27.125 nC₃H₇ iC₃H₇ nC₄H₉ I.27.126 nC₃H₇ iC₃H₇ CH₂CH(CH₃)₂ I.27.127 nC₃H₇ iC₃H₇ CH(CH₃)C₂C₅ I.27.128 nC₃H₇ iC₃H₇ CH₂CH═CH₂ I.27.129 nC₃H₇ iC₃H₇ CH₂C≡CH I.27.130 nC₃H₇ nC₄H₉ nC₄H₉ I.27.131 nC₃H₇ nC₄H₉ CH₂CH(CH₃)₂ I.27.132 nC₃H₇ nC₄H₉ CH(CH₃)C₂C₅ I.27.133 nC₃H₇ nC₄H₉ CH₂CH═CH₂ I.27.134 nC₃H₇ nC₄H₉ CH₂C≡CH I.27.135 nC₃H₇ CH₂CH(CH₃)₂ CH₂CH(CH₃)₂ I.27.136 nC₃H₇ CH₂CH(CH₃)₂ CH(CH₃)C₂C₅ I.27.137 nC₃H₇ CH₂CH(CH₃)₂ CH₂CH═CH₂ I.27.138 nC₃H₇ CH₂CH(CH₃)₂ CH₂C≡CH I.27.139 nC₃H₇ CH(CH₃)C₂C₅ CH(CH₃)C₂C₅ I.27.140 nC₃H₇ CH(CH₃)C₂C₅ CH₂CH═CH₂ I.27.141 nC₃H₇ CH(CH₃)C₂C₅ CH₂C≡CH I.27.142 nC₃H₇ CH₂CH═CH₂ CH₂CH═CH₂ I.27.143 nC₃H₇ CH₂CH═CH₂ CH₂C≡CH I.27.144 nC₃H₇ CH₂C≡CH CH₂C≡CH I.27.145 iC₃H₇ C₂H₅ C₂H₅ I.27.146 iC₃H₇ C₂H₅ nC₃H₇ I.27.147 iC₃H₇ C₂H₅ iC₃H₇ I.27.148 iC₃H₇ C₂H₅ nC₄H₉ I.27.149 iC₃H₇ C₂H₅ CH₂CH(CH₃)₂ I.27.150 iC₃H₇ C₂H₅ CH(CH₃)C₂C₅ I.27.151 iC₃H₇ C₂H₅ CH₂CH═CH₂ I.27.152 iC₃H₇ C₂H₅ CH₂C≡CH I.27.153 iC₃H₇ nC₃H₇ nC₃H₇ I.27.154 iC₃H₇ nC₃H₇ iC₃H₇ I.27.155 iC₃H₇ nC₃H₇ nC₄H₉ I.27.156 iC₃H₇ nC₃H₇ CH₂CH(CH₃)₂ I.27.157 iC₃H₇ nC₃H₇ CH(CH₃)C₂C₅ I.27.158 iC₃H₇ nC₃H₇ CH₂CH═CH₂ I.27.159 iC₃H₇ nC₃H₇ CH₂C≡CH I.27.160 iC₃H₇ iC₃H₇ iC₃H₇ I.27.161 iC₃H₇ iC₃H₇ nC₄H₉ I.27.162 iC₃H₇ iC₃H₇ CH₂CH(CH₃)₂ I.27.163 iC₃H₇ iC₃H₇ CH(CH₃)C₂C₅ I.27.164 iC₃H₇ iC₃H₇ CH₂CH═CH₂ I.27.165 iC₃H₇ iC₃H₇ CH₂C≡CH I.27.166 iC₃H₇ nC₄H₉ nC₄H₉ I.27.167 iC₃H₇ nC₄H₉ CH₂CH(CH₃)₂ I.27.168 iC₃H₇ nC₄H₉ CH(CH₃)C₂C₅ I.27.169 iC₃H₇ nC₄H₉ CH₂CH═CH₂ I.27.170 iC₃H₇ nC₄H₉ CH₂C≡CH I.27.171 iC₃H₇ CH₂CH(CH₃)₂ CH₂CH(CH₃)₂ I.27.172 iC₃H₇ CH₂CH(CH₃)₂ CH(CH₃)C₂C₅ I.27.173 iC₃H₇ CH₂CH(CH₃)₂ CH₂CH═CH₂ I.27.174 iC₃H₇ CH₂CH(CH₃)₂ CH₂C≡CH I.27.175 iC₃H₇ CH(CH₃)C₂C₅ CH(CH₃)C₂C₅ I.27.176 iC₃H₇ CH(CH₃)C₂C₅ CH₂CH═CH₂ I.27.177 iC₃H₇ CH(CH₃)C₂C₅ CH₂C≡CH I.27.178 iC₃H₇ CH₂CH═CH₂ CH₂CH═CH₂ I.27.179 iC₃H₇ CH₂CH═CH₂ CH₂C≡CH I.27.180 iC₃H₇ CH₂C≡CH CH₂C≡CH

Extraordinary preference is also given to the compounds of formula I.28, in particular to the compounds of formulae I.28.1 to I.28.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is CH₃.

Extraordinary preference is also given to the compounds of formula I.29, in particular to the compounds of formulae I.29.1 to I.29.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is C₂H₅.

Extraordinary preference is also given to the compounds of formula I.30, in particular to the compounds of formulae I.30.1 to I.30.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is nC₃H₇.

Extraordinary preference is also given to the compounds of formula I.31, in particular to the compounds of formulae I.31.1 to I.31.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is iC₃H₇.

Extraordinary preference is also given to the compounds of formula I.32, in particular to the compounds of formulae I.32.1 to I.32.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is CH₂CH(CH₃)₂.

Extraordinary preference is also given to the compounds of formula I.33, in particular to the compounds of formulae I.33.1 to I.33.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is CH(CH₃)C₂H₅.

Extraordinary preference is also given to the compounds of formula I.34, in particular to the compounds of formulae I.34.1 to I.34.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is tC₄H₉.

Extraordinary preference is also given to the compounds of formula I.35, in particular to the compounds of formulae I.35.1 to I.35.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is CH(CH₃)CH═CH₂.

Extraordinary preference is also given to the compounds of formula I.36, in particular to the compounds of formulae I.36.1 to I.36.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is C(CH₃)CH═CH₂.

Extraordinary preference is also given to the compounds of formula I.37, in particular to the compounds of formulae I.37.1 to I.37.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is CH₂C≡CH.

Extraordinary preference is also given to the compounds of formula I.38, in particular to the compounds of formulae I.38.1 to I.38.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is CH(CH₃)C≡CH.

Extraordinary preference is also given to the compounds of formula I.39, in particular to the compounds of formulae I.39.1 to I.39.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is 3-tetrahydrofuranyl.

Extraordinary preference is also given to the compounds of formula I.40, in particular to the compounds of formulae I.40.1 to I.40.180, which differ from the corresponding compounds of formulae I.27.1 to I.27.180 in that R^(c) is 4-tetrahydropyranyl.

Extraordinary preference is also given to the compounds of formula I.41 (corresponds to formula I wherein R¹ is NR^(b)R^(c) wherein R^(b) and R^(c) from a 1,4-butandiyl-chain and R⁴ is hydrogen), in particular to the compounds of formulae I.41.1 to I.41.36 of table 3, where the definitions of the variables R¹ to R⁴ are of particular importance for the compounds according to the invention not only in combination with one another but in each case on their own. TABLE 3 I.41

No. R² R³ I.41.1 C₂H₅ C₂H₅ I.41.2 C₂H₅ nC₃H₇ I.41.3 C₂H₅ iC₃H₇ I.41.4 C₂H₅ nC₄H₉ I.41.5 C₂H₅ CH₂CH(CH₃)₂ I.41.6 C₂H₅ CH(CH₃)C₂H₅ I.41.7 C₂H₅ CH₂CH═CH₂ I.41.8 C₂H₅ CH₂C≡CH I.41.9 nC₃H₇ nC₃H₇ I.41.10 nC₃H₇ iC₃H₇ I.41.11 nC₃H₇ nC₄H₉ I.41.12 nC₃H₇ CH₂CH(CH₃)₂ I.41.13 nC₃H₇ CHCH₃)C₂H₅ I.41.14 nC₃H₇ CH₂CH═CH₂ I.41.15 nC₃H₇ CH₂C≡CH I.41.16 iC₃H₇ iC₃H₇ I.41.17 iC₃H₇ nC₄H₉ I.41.18 iC₃H₇ CH₂CH CH₃)₂ I.41.19 iC₃H₇ CH(CH₃)C₂H₅ I.41.20 iC₃H₇ CH₂CH═CH₂ I.41.21 iC₃H₇ CH₂C≡CH I.41.22 nC₄H₉ nC₄H₉ I.41.23 nC₄H₉ CH₂CH(CH₃)₂ I.41.24 nC₄H₉ CH(CH₃)C₂H₅ I.41.25 nC₄H₉ CH₂CH═CH₂ I.41.26 nC₄H₉ CH₂C≡CH I.41.27 CH₂CH(CH₃)₂ CH₂CH(CH₃)₂ I.41.28 CH₂CH(CH₃)₂ CH(CH₃)C₂H₅ I.41.29 CH₂CH(CH₃)₂ CH₂CH═CH₂ I.41.30 CH₂CN(CH₃)₂ CH₂C≡CH I.41.31 CH(CH₃)C₂H₅ CH(CH₃)C₂H₅ I.41.32 CH(CH₃)C₂H₅ CH₂CH═CH₂ I.41.33 CH(CH₃)C₂H₅ CH₂C≡CH I.41.34 CH₂CH═CH₂ CH₂CH═CH₂ I.41.35 CH₂CH═CH₂ CH₂C≡CH I.41.36 CH₂C≡CH CH₂C≡CH

Extraordinary preference is also given to the compounds of formula I.42, in particular to the compounds of formulae I.42.1 to I.42.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is NR^(b)R^(c) wherein R^(b) and R^(c) form a 1,5 pentanediyl-chain.

Extraordinary preference is also given to the compounds of formula I.43, in particular to the compounds of formulae I.43.1 to I.43.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is NR^(b)R^(c) wherein R^(b) and R^(c) form a 1,6-hexanediyl-chain.

Extraordinary preference is also given to the compounds of formula I.44, in particular to the compounds of formulae I.44.1 to I.44.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is CH₃.

Extraordinary preference is also given to the compounds of formula I.45, in particular to the compounds of formulae I.45.1 to I.45.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is C₂H₅.

Extraordinary preference is also given to the compounds of formula I.46, in particular to the compounds of formulae I.46.1 to I.46.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is nC₃H₇.

Extraordinary preference is also given to the compounds of formula I.47, in particular to the compounds of formulae I.47.1 to I.47.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is iC₃H₇.

Extraordinary preference is also given to the compounds of formula I.48, in particular to the compounds of formulae I.48.1 to I.48.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is CH₂CH(CH₃).

Extraordinary preference is also given to the compounds of formula I.49, in particular to the compounds of formulae I.49.1 to I.49.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is CH(CH₃)C₂H₅.

Extraordinary preference is also given to the compounds of formula I.50, in particular to the compounds of formulae I.50.1 to I.50.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is tC₄H₉.

Extraordinary preference is also given to the compounds of formula I.51, in particular to the compounds of formulae I.51.1 to I.51.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is CH(CH₃)CH═CH₂.

Extraordinary preference is also given to the compounds of formula I.52, in particular to the compounds of formulae I.52.1 to I.52.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is C(CH₃)₂CH═CH₂.

Extraordinary preference is also given to the compounds of formula I.53, in particular to the compounds of formulae I.53.1 to I.53.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is CH₂C≡CH.

Extraordinary preference is also given to the compounds of formula I.54, in particular to the compounds of formulae I.54.1 to I.54.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is CH(CH₃)C≡CH.

Extraordinary preference is also given to the compounds of formula I.55, in particular to the compounds of formulae I.55.1 to I.55.36, which differ from the corresponding compounds of formulae I.41.1 to I.41.36 in that R¹ is SR^(d) wherein R^(d) is 3-tetrahydrofuranyl.

In the synthesis of the α-cyanoacrylates, the starting materials or products in question are usually present in an (E):(Z) ratio of from 95:5 to 5:95. It is possible to separate the isomers, for example by chromatographic purification, and to continue the reactions with the pure isomer in question.

The α-cyanoacrylates of formula I can be prepared by various routes, for example by the following processes:

Process A

Cyanoacetic derivatives of formula IV are reacted with carbonyl chlorides of the formula V to give enols of the formula III. Following conversion of the enol OH-group, the corresponding enol ether of the formula II is obtained, which is then converted with ammonia into the desired α-cyanoacrylate:

where R⁵ is for example methyl, ethyl or benzyl

Preferably compounds of formula I wherein R¹ is OR^(a) are prepared according to this process. However compounds of formula I wherein R¹ is NR^(b)R^(c) or SR^(d) can be prepared analogous.

The conversion of the cyanoacetic ester of formula IV with carbonyl chlorides of formula V into enols of the-formula III is usually carried out at temperatures of from 0° C. to 15° C., preferably at 0° C., in an inert organic solvent, if appropriate in the presence of a base [cf. Haller et al., C. R. Acad. Sc. 15 (1887), 115; Dieckmann et al., Chem. Ber. 37 (1904), 3384; Michael et al., Chem. Ber. 38 (1905), 50; Guinchant, Ann. Chim. 9 (1918), 49].

Suitable solvents are aliphatic hydrocarbons such as pentane, hexane, cyclohexane and mixtures of C₅-C₈-alkanes, aromatic hydrocarbons, such as toluene, o-, m- and p-xylene, halogenated hydrocarbons, such as methylene chloride, chloroform and chlorobenzene, ethers, such as diethyl ether, diisopropyl ether, tert-butyl methyl ether, dioxane, anisole and tetrahydrofuran, nitriles, such as acetonitrile and propionitrile, particularly preferably methylene chloride, tert-butyl methyl ether, diethyl ether, tetrahydrofuran and acetonitrile.

It is also possible to use mixtures of solvents mentioned.

Suitable bases are, in general, inorganic compounds, such as alkali metal and alkaline earth metal alkoxides, such as sodium methoxide, sodium ethoxide, potassium ethoxide, potassium tert-butoxide, potassium tert-pentoxide and dimethoxymagnesium, and furthermore organic bases, for example tertiary amines, such as trimethylamine, triethylamine, diisoproylethylamine and N-methylpiperidine, pyridine, substituted pyridines such as collidine, lutidine, N-methylmorpholine and 4-dimethylaminopyridine, and also bicyclic amines. Particular preference is given to sodium ethoxide and triethylamine.

The bases are generally employed in excess or they can, if appropriate, be used as solvent.

IV is generally employed in excess, based on V.

The reaction mixtures are worked up in a customary manner, for example by mixing with water, separation of the phases and, if appropriate, chromatographic purification of the crude products. Some of the intermediates and end products are obtained in the form of viscous oils which can be purified or freed from volatile components under reduced pressure and at moderately elevated temperature. If the intermediates and end products are obtained as solid, purification can also be carried out by recrystallization or digestion.

The enol ethers of formula II can be obtained by alkylation of the silver salt of the enol of the formula III.

The reaction of the enol of formula III with silver nitrate is usually carried out in water at 25° C. [cf. Haller, Comp. Rend. 130 (1900), 1221].

The reaction of the silver salt of the enol of formula III with an alkylating agent is usually carried out at from 25° C. to 80° C. in an inert organic solvent [cf. Haller, Comp. Rend. 130 (1900), 1221].

Suitable solvents are halogenated hydrocarbons, such as methylene chloride, chloroform and chlorobenzene, ethers, such as diethyl ether, diisopropyl ether, tert-butyl methyl ether, dioxane, anisole and tetrahydrofuran, and nitriles, such as acetonitrile and propionitrile, particularly preferably acetonitrile.

It is also possible to use mixtures of the solvents mentioned.

Suitable alkylating agents R⁵-halides are alkyl halides with R⁵═C₁-C₆-alkyl, such as, for example, methyl or ethyl iodide and also methyl or ethyl bromide. For converting III into II, it is furthermore also possible to use benzyl halides with R⁵=benzyl, such as, for example, benzyl chloride or benzyl bromide.

In general, the alkylating agent is employed in an excess, based on the silver salt of the acrylocyanoacetic ester of formula III.

Work-up can be carried out in a manner known per se to afford the product.

For obtaining the enol ether of formula II wherein R⁵ is methyl, the enol of formula III can also be reacted with diazomethane. This reaction is usually carried out at from 0° C. to 20° C. in an inert organic solvent [cf. Arndt et al., Liebigs Ann. 521 (1936), 108].

Suitable solvents are ethers, such as diethyl ether, diisopropyl ether, tert-butyl methyl ether, dioxane, anisole and tetrahydrofuran, particularly preferably diethyl ether.

It is also possible to use mixtures of the solvents mentioned.

The starting materials are generally reacted with each other in equimolar amounts. It may be advantageous to employ an excess of diazomethane, based on the enol of formula III.

Instead of diazomethane, it is also possible to use, for example, trimethylsilyldiazomethane.

Work-up can be carried out in a manner known per se to afford the product.

The enol ethers of formula II can also be obtained by reacting, for example, orthoesters of formula VII, where R⁵ is a C₁-C₄-alkyl radical, such as, for example, methyl or ethyl, with the appropriate cyanoacetic esters of formula IV:

where R⁵═C₁-C₄-alkyl

This reaction is usually carried out at from 100° C. to 150° C., preferably at from 110° C. to 130° C., in the presence of a carboxylic anhydride [cf. Xia et al., J. Med. Chem. 40 (1997), 4372].

Suitable solvents are carboxylic anhydrides, such as acetic anydride or propionic anhydride.

In general, an excess of VII is employed, based on IV.

The orthoesters required for preparing the compounds VI are known from the literature [cf. Houben-Weyl, 1965, Vol. 6/3, 300 f.], or they can be prepared in accordance with the literature cited and/or are commercially available.

The reaction of the enol ethers of formula II with ammonia or an ammonia-containing solution is usually carried out at from 0° C. to 20° C., preferably from 0° C. to 10° C., in an inert organic solvent [cf. Haller, Comp. Rend. 130 (1900), 1221].

Suitable solvents are ethers, such as diethyl ether, diisopropyl ether, tert-butyl methyl ether, dioxane, anisole and tetrahydrofuran, nitriles, such as acetonitrile and propionitrile, alkohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol and tert-butanol, particularly preferably acetonitrile.

It is also possible to use mixtures of the solvents mentioned.

In general, an excess of ammonia is employed, based on II.

Work-up can be carried out in a manner known per se to afford the product.

The starting materials required for preparing the compounds I are known from the literature [Dahn et al., Helv. Chim. Acta 42 (1959), 1214; Bowie, Tetrahedron 23 (1967), 305], or they can be prepared in accordance with the literature cited and/or are commercially available.

Process B

Enols of formula III are reacted with acid chlorides R⁶COCl to give enol derivates of the formula VI, which are then reacted with ammonia to give the desired α-cyanoacrylates:

Preferably compounds of formula I wherein R¹ is OR^(a) are prepared according to this process. However compounds of formula I wherein R¹ is NR^(b)R^(c) or SR^(d) can be prepared analogous.

R⁶COCl are customary acid chlorides which are commercially available, such as, for example, acetic acid chlorid, isobutyryl chloride or pivaloyl chloride. R⁶ is C₁-C₆-alkyl (such as, for example, methyl, ethyl, isopropyl or tert.-butyl), phenyl or benzyl. Preference is given to acid chlorides having sterically demanding radicals R⁶, such as, for example, branched C₃-C₆-alkyl or phenyl.

The conversion of the enols of formula III with acid chlorides into enol esters of formula VI is usually carried out at from 0° C. to 35° C., preferably at 25° C., in an inert organic solvent in the presence of a base [cf. Haller, Comp. Rend. 130 (1900), 1221; Schmitt, Bull. Soc. Chim. France 31 (1904), 325].

Suitable solvents are aromatic hydrocarbons, such as toluene, o-, m- and p-xylene, halogenated hydrocarbons, such as methylene chloride, chloroform and chlorobenzene, ethers, such as diethyl ether, diisopropyl ether, tert-butyl methyl ether, dioxane, anisole and tetrahydrofuran, nitriles, such as acetonitrile and propionitrile, particularly preferably acetonitrile.

It is also possible to use mixtures of the solvents mentioned.

Optionally the reaction can be carried out in the presence of a base.

Suitable bases are, in general, inorganic compounds, such as alkali metal and alkaline earth metal hydrides, such as lithium hydride, sodium hydride, potassium hydride and calcium hydride, alkali metal and alkaline earth metal carbonates, such as lithium carbonate, potassium carbonate and calcium carbonate, and also alkali metal and alkaline earth metal alkoxides, such as sodium methoxide, sodium ethoxide, potassium ethoxide, potassium tert-butoxide, potassium tert-pentoxide and dimethoxymagnesium, furthermore organic bases, for example tertiary amines, such as trimethylamine, triethylamine, diisopropylethylamine, N-methyl-piperidine, pyridine, substituted pyridines, such as collidine, lutidine and 4-dimethylaminopyridine, and also bicyclic amines. Particular preference is given to alkoxides.

The bases are generally employed in equimolar amounts.

The starting materials are generally reacted with one another in equimolar amounts. It may be advantageous to employ an excess of acid chloride, based on III.

Work-up can be carried out in a manner known per se to afford the product.

The enols of the formula III required for preparing the compounds VI can be prepared according to Process A.

The reaction of the enol esters of the formula VI with ammonia or an ammonia-containing solution is carried out under-the same conditions as described in Process A.

Process C

Reaction of the enols of formula III with POCl₃ and subsequent reaction of the crude reaction mixture with ammonia likewise gives α-cyanoacrylates of formula I:

Preferably compounds of formula I wherein R¹ is OR^(a) are prepared according to this process. However compounds of formula I wherein R¹ is NR^(b)R^(c) or SR^(d) can be prepared analogous.

The reaction with POCl₃ is usually carried out at from 0° C. to 100° C., preferably at 0 to 50° C., particular preferably 0 to 25° C., most preferably at 0° C., in an inert organic solvent in the presence of a base [cf. DE 1 935 630].

Suitable solvents for the reaction with POCl₃ are aromatic hydrocarbons, such as toluene, o-, m- and p-xylene, halogenated hydrocarbons, such as methylene chloride, chloroform and chlorobenzene, particularly preferably methylene chloride, chloroform and toluene.

It is also possible to use mixtures of the solvents mentioned.

Suitable bases are, in general, organic bases, for example tertiary amines, such as trimethylamine, triethylamine, diisopropylethylamine, N-methylpiperidine, pyridine, substituted pyridines, such as collidine, lutidine and 4-dimethylaminopyridine, and also bicyclic amines. Particular preference is given to triethylamine.

The bases are generally employed in excess.

Following gentle concentration of the reaction mixture, the subsequent reaction, with ammonia, of the enol phosphate formed in the reaction is preferably carried out in nitriles, such as acetonitrile or propionitrile.

In general, an excess of POCl₃ and NH₃ is used, based on III.

Process D

The reaction of imido esters of formula VIII, previously released, for example, from the corresponding hydrochlorides using a base, with cyanoacetic derivatives of formula IV also gives α-cyanoacrylates of formula I:

where R⁷═C₁-C₆-alkyl

Preferably compounds of formula I wherein R¹ is OR^(a) are prepared according to this process. However compounds of formula I wherein R¹ is NR^(b)R^(c) or SR^(d) can be prepared analogous.

R⁷ is a C₁-C₆-alkyl radical such as, for example, methyl or ethyl.

The imido esters are usually released from their salts using bases, such as potassium carbonate [cf. Houben-Weyl 1952, Vol. 8, 697].

The reaction with cyanoacrylates of formula IV is usually carried out at from 50° C. to 100° C., preferably at from 80° C. to 90° C., in an organic solvent [cf. Kenner et al., J. Chem. Soc. 1943, 388].

Suitable solvents are ethers, such as dioxane, anisole and tetrahydrofuran, nitriles, such as acetonitrile and propionitrile, alcohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol and tert-butanol, particularly preferably ethanol.

It is also possible to use mixtures of other solvents mentioned.

The starting materials are generally reacted with one another in equimolar amounts. It may be advantageous to employ an excess of VIII, based on IV.

The imido ester hydrochlorides required for preparing the compounds I are known from the literature [cf. Pinner, Die Iminoäther und ihre Derivate, [The imino ethers and their derivatives], Berlin 1892] or they can be prepared in accordance with the literature cited, especially from the respective nitriles.

Process E

The reaction of amidines of formula IX, previously released, for example, from the corresponding hydrochlorides using a base, with cyanoacetic derivatives of formula IV also gives α-cyanoacrylates of formula I:

Preferably compounds of formula I wherein R¹ is OR^(a) are prepared according to this process. However compounds of formula I wherein R¹ is NR^(b)R^(c) or SR^(d) can be prepared analogous.

The amidines are usually released from their salts using bases, such as, for example, potassium carbonate [cf. Houben-Weyl 1952, Vol. 8, 702].

The reaction with cyanoacrylates of formula IV is usually carried out at from 80° C. to 130° C., preferably at from 90° C. to 100° C., in an inert organic solvent [cf. Hull et al., J. Chem. Soc. 1946, 357].

Suitable solvents are aromatic hydrocarbons, such as toluene, o-, m- and p-xylene, alcohols, such as ethanol, n-propanol, isopropanol, n-butanol and tert-butanol, particularly preferably ethanol.

Suitable bases for releasing the amidines from their salts are, in general, inorganic compounds, such as alkali metal and alkaline earth metal carbonates, such as lithium carbonate, potassium carbonate and calcium carbonate, and also alkali metal and alkaline earth metal alkoxides, such as sodium methoxide, sodium ethoxide, potassium ethoxide, potassium tert-butoxide, potassium tert-pentoxide, and furthermore ammonia. Particular preference is given to potassium carbonate and ammonia.

The starting materials are generally reacted with one another in equimolar amounts. It may be advantageous to employ an excess of IX, based on IV.

The amidine hydrochlorides required for preparing the compounds I are known from the literature [Houben-Weyl; 1952, Vol. 8, 702 f.], or they can be prepared in accordance with the literature cited, especially from the respective nitriles.

Process F

Enaminonitriles of formula X are reacted with phosgene (COCl₂) to give the corresponding acid chloride of formula XI, which is then reacted with a compound of formula XII in the presence of a base to give the α-cyanoacrylates of formula I:

The reaction with phosgene is usually carried out at from 20° C. to 120° C., preferably at from 25° C. to 85° C., in inert organic solvent [cf.Ohoka et al, J. Org. Chem. 38, 1973, 2287].

Suitable solvents are aliphotic hydrocarbons, such as pentane, hexane, cyclohexane and mixtures of C₅-C₈-alkanes, aromatic hydrocarbons, such as toluene, o-, m- and p-xylene, halogenated hydrocarbons, such as methylene chloride, chloroform and chlorobenzene, ethers, such as diethyl ether, diisopropyl ether, anisole and tetrahydrofuran, nitriles, such as acacetonitrile and propionitrile, particulary preferably aromatic hydrocarbons such as toluene.

It is also possible to use nitriles of solvents mentioned.

Phosgene is generally employed in excess based on X, preferably are used 4 equivalents of phosgene.

It is also possible to use equivalents of phosgene like diphosgene or triphosgene. Preferred is phosgene.

Works up can be carried out in a manner known per se to afford the product.

The starting materials required for preparing the enaminonitrile of formular X are known from the literature [Fomum et al, J. Chem. Soc. Perkin Trans 1, 1973.1108], or they can be prepared in accerdance with the literature cited.

The reacted of the said chloride of formula XI with a compund of formula XII is usually carried and at temperatures of from 0° C. to 50° C., preferably of from 10° C. to 25° C., in an inert organic solvent in the presence of a base [cf. Ohoka et al., J. Org. Chem. 38,1973, 2287].

Suitable solvents are aliphatic hydrocarbons such as pentane, hexane, cyclohexane and mixtures of C₅-C₆-alkanes, aromatic hydrocarbons, such as toluene, o-, m-, and p-xylene, halogenoted hydrocarbons, such as methylene chloride, chloroform and chlorobenzol, ethers, such as diethyl ether, diisopropyl ether, tert.-butyl methyl ether and tetrahydrofuran, nitriles, such as acetonitril and propionitrile, particularly preferably tetrahydrofuran, toluene and tert.-butyl methyl ether.

It is also possible to use mixtures of solvents mentioned.

Suitable bases are, in general, inorganic compounds, such as alkali metal and alkaline earth metal carbonates, such as lithium carbonate, sodium carbonate, potassium carbonate and calcium carbonate; and also alkali metal, hydrogencarbonates, such as sodium hydrogen carbonate; furthermore organic bases, for example tertiary amines, such as trimethylamine, triethylamine, diisopropylethylamine, N-methylpiperidine, pyridine, substituted pyridines such as collidine, lutidine and 4-dimethylaminopyridine, and also bicylic amines. Particular preference is given to trimethylamine.

The bases are generally empolyed in equimolar amounts.

The starting materials are generally reacted with one another in equimolar amounts. It may be advantogeons to empolyan acess of XII based on XI.

α-cyonoacrylates of formula I wherein R¹ is OR^(a) with R^(a) is hydrogen can for example be prepared by hydrolysis of the respective acid chloride (see Houben-Weyl, 1952, Vol. 8, 425 f) or by hydrolysis of the respective ester (see Houben-Weyl, 1952, Vol. 8, 421 f).

The resulting acid can be transformed by common methods into desired ester derivatives. (Houben-Weyl, 1952, Vol. 8, 516 f, 522 f).

The present invention also provides novel enol ethers of formula II

where R¹ to R⁴ have the meanings mentioned for the compounds of the formula I and R⁵ is C₁-C₆-alkyl (such as, for example, methyl or ethyl) or benzyl.

The enol ethers of formula II are present as an (E)/(Z) mixture in a ratio of from 95:5 to 5:95. It is possible to separate the isomers, for example by chromatographic methods.

With respect to the variables, the particularly preferred embodiments of the intermediates correspond to those of radicals R¹ to R⁴ of formula I.

Particular preference is given to the compounds of formula II in wherein R¹ is OR^(a) wherein

-   -   R^(a) is branched C₃-C₆-alkyl;         -   particularly preferably 1-methylethyl, 2-methylpropyl or             1,1-dimethylethyl; and     -   R² is C₁-C₄-alkyl;         -   particularly preferably methyl, ethyl or n-propyl;         -   especially preferably methyl or ethyl;     -   R³ is C₂-C₄-alkyl;         -   particularly preferably ethyl or n-propyl;         -   especially preferably ethyl or n-propyl; and     -   R⁴ is hydrogen, fluorine or chlorine;         -   particularly preferably hydrogen.

Particular preference is also given to compounds of formula II wherein R¹ is NR^(b)R^(c) wherein

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;     -   R² is C₁-C₄-alkyl;         -   preferably methyl, ethyl, or n-propyl;     -   R³ is C₂-C₄-alkyl;         -   preferably ethyl or n-propyl; and     -   R⁴ is hydrogen.

Particular preference is also given to compounds of formular II wherein R¹ is SR^(d) wherein

-   -   R^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;     -   R² is C₁-C₄-alkyl;         -   preferably methyl, ethyl, or n-propyl;     -   R³ is C₂-C₄-alkyl,         -   preferably ethyl or n-propyl; and     -   R⁴ is hydrogen.

The present invention also provides novel enol esters of formula VI

where R¹ to R⁴ have the meanings mentioned for the compounds of formula I and R⁶ is C₁-C₆-alkyl, (such as, for example, isopropyl or tert-butyl, preferably tert-butyl), phenyl or benzyl.

The enol esters of formula VI are present as an (E)/(Z) mixture in a ratio of from 95:5 to 5:95, usually in a ratio of 50:50. It is possible to separate the isomers, for example by chromatographic methods.

With respect to the variables, the particularly preferred embodiments of the intermediates correspond to those of radicals R¹ to R⁴ in the formula I.

Particular preference is given to the compounds of formula VI in wherein R¹ is OR^(a) wherein

-   -   R^(a) is branched C₃-C₆-alkyl;         -   particularly preferably 1-methylethyl, 2-methylpropyl or             1,1-dimethylethyl; and     -   R² is C₁-C₄-alkyl;         -   particularly preferably methyl, ethyl or n-propyl;         -   especially preferably methyl or ethyl;         -   also especially preferably ethyl or n-propyl;     -   R³ is C₂-C₄-alkyl;         -   particularly preferably ethyl; and     -   R⁴ is hydrogen, fluorine or chlorine;         -   particularly preferably hydrogen.

Particular preference is also given to compounds of formular VI wherein R¹ is NR^(b)R^(c) wherein

-   -   R^(b) and R^(c) are independently of each other hydrogen or         C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;     -   R² is C₁-C₄-alkyl;         -   preferably methyl, ethyl, or n-propyl;     -   R³ is C₂-C₄-alkyl;         -   preferably ethyl or n-propyl; and     -   R⁴ is hydrogen.

Particular preference is also given to compounds of formular VI wherein R¹ is SR^(d) wherein

-   -   R^(d) is hydrogen or C₁-C₆-alkyl;         -   preferably hydrogen or C₁-C₄-alkyl;         -   particular preferably hydrogen, ethyl, n-propyl or i-propyl;     -   R² is C₁-C₄-alkyl;         -   preferably methyl, ethyl, or n-propyl;     -   R³ is C₂-C₄-alkyl;         -   preferably ethyl or n-propyl; and     -   R⁴ is hydrogen.

EXAMPLE 4.1 Isopropyl (2Z)-3-amino-2-cyano-4-ethyl-2-hexenoate

According to Process C:

1. Isopropyl (2Z)-3-hydroxy-2-cyano-4-ethyl-2-hexenoate

22.2 g (0.16 mol) of 2-ethylbutyryl chloride were added to a solution of 21 g (0.16 mol) of isopropyl cyanoacetate in CH₂Cl₂, and the reaction mixture was cooled to 0° C. At this temperature, with ice-cooling, 33.5 g (0.33 mol) of triethylamine were added dropwise, and the mixture was then stirred at 25° C. for 2 h. Following subsequent acidic hydrolysis, the organic phase was washed, dried and concentrated. Purification by customary methods gave 24.4 g of the title compound (68% of theory) as a colorless oil (b.p. 70-75° C./1.5 mbar).

2. Isopropyl (2Z)-3-amino-2-cyano-4-ethyl-2-hexenoate

24.4 g (0.11 mol) of isopropyl (2Z)-3-hydroxy-2-cyano-4-ethyl-2-hexenoate were dissolved in CH₂Cl₂ and, at 25° C., 33.2 g (0.22 mol) of POCl₃ were added. After cooling to 0° C., 43.8 g (0.44 mol) of triethylamine were added dropwise, and the mixture was stirred at 25° C. for 2 h. The solution was then concentrated and the residue was taken up in acetonitrile and cooled to 0° C., and 30 g (0.44 mol) of a 25 percent strength solution of ammonia were added dropwise. After 2 h of stirring, the mixture was concentrated to dryness, the residue was taken up in MTBE (methyl tert-butyl ether) and the organic phase was washed with NaOH and water, dried and concentrated. Purification by customary methods gave 10 g (40% of theory) of the title compound as a colorless solid (m.p. 140° C.).

According to Process F:

1. 3-Amino-2-cyano-4-ethyl-2-hexene

13.1 g (94 mmol) of 1-Cyano-3-ethyl-2-oxo-pentane were dissolved in toluene and 15 g (194 mmol) ammonium acetate and 1 ml dry acetic acid were added. The mixture was reflured 2 h and then cooled to room temperature. The mixture was washed, dried and concentrated. Perification by customary methods gove 13. 1 g (100% of theory) of the title compound as a oil.

2. (2Z)-3-Amino-2-cyano-4-ethyl-2-hexenoyl chloride

250 ml toluene were cooled to 0° C. and 40 g (0.4 mol) of phosgene were added. After warming up to 25° C., 13.8 g (0.1 mol) of 3-amino-2-cyano-4-ethyl-2-hexene in toluene were added. The reaction mixture was heated at 70° C. for 4 h, then the unreacted phosgene was removed by blowing out with dry N₂. After cooling to 25° C. the product precipitated. Filtration and washing with diethyl ether gave 12 g (60% of theory) of the title compound as a yellow solid (m. p. 102° C.).

3. Isopropyl (2Z)-3-amino-2-cyano-4-ethyl-2-hexenoate

12 g (60 mmol) of (2Z)-3-amino-2-cyano-4-ethyl-2-hexenoyl chloride were dissolved in CH₂Cl₂ and 3.6 g (60 mmol) of isopropanole were added. At 20° C. to 25° C. 6.1 g (60 mmol) of triethylamine were added dropwise and the solution was stirred at 25° C. for 4 h. The solution was washed with water, the organic phase was seperated, dried and concentrated. Crystallisation from diisopropyl ether gave 12.4 g of the title compound (92% of theory) as a colorless solid (m.p. 140° C.).

EXAMPLE 4.14 3-Oxetanyl (2Z)-3-amino-2-cyano-4-ethyl-2-hexenoat

According to Process A:

1. 3-Oxetanyl-cyanoethanoate

23.2 g (0.29 mol) of 3-oxetanol and 3 g (0.025 mol) of dimethylaminopyridine were added to a solution of 25 g (0.-29 mol) of cyanoacetic acid in CH₂Cl₂. After cooling to 0° C., 66.8 g (0.32 mol) of dicyclohexylcarbodiimide (DCC) in CH₂Cl₂ were added dropwise and the reaction micxture was stirred at 25° C. for 2 h. The solid was removed and the solution was concentrated. Purification by customary methods gave 42 g of the title compound (100% of theory) as a colorless oil.

2. 3-Oxetanyl (2Z)-2-cyano-4-ethyl-3-hydroxy-2-hexanoate

42 g (0.29 mol) of 3-oxetanyl-cyanoethanoat were dissolved in CH₂Cl₂ and 39 g (0.29 mol) of 2-ethyl-butanoyl cloride were added. The mixture was coold to 0° C. and 29.3 g (0.29 mol) of triethylamine were added. The reaction mixture was stirred at 25° C. for 2 h. Following subsequent acidic hydrolysis the organic phase was washed, dried and concentrated. Purification by customary methods gave 41.5 g of the title compound (60% of theory) as a reddish oil.

3. 3-Oxetanyl (2Z)-3-amino-2-cyano-4-ethyl-2-hexanoat

5 g (21 mmol) of 3-oxetanyl (2Z)-2-cyano-4-ethyl-2-hexanoat were dissolved in acetonitrile and 30 mmol of diazomethane in ether were added at 25° C. After 10 min 50 ml (0.65 mol) of a 25% ammonia solution were added and the reaction mixture was stirred for 1 h. Following subsequent addition of tert.-butyl methyl ether, the organic phase was washed, dried and concentrated. Crystallisation from diisopropyl ether gave 2 g of the title compound (40% of theory) as a colorless solid (m. p. 175° C.).

EXAMPLE 4.42 (2Z)-3-Amino-2-cyano-4-ethyl-2-hexene acid

3 g (15 mmol) of (2Z)-3-amino-2-cyano-4-ethyl-2-hexenoyl chloride dissolved in acetonitrile were added dropwise to a solution of 2.6 g (30 mmol) NaHCO₃ in water. The solution was stirred at 25° C. for 30 min, then concentrated to dryness and the residue was taken up in methanol. The precipitate was seperated and the filtrate concencentrated to dryness again. The residue was dissolved in water and saturated KHSO4-solution was added. Filtration of the precipitate gave 2 g of the title compound (73% of theory) as a colorless solid (m. p. 150° C.)

The compounds listed in Table 4 below can be prepared analogously to the above mentioned exemples: TABLE 4

Example No. R^(a) m.p. [° C.] 4.1  iC₃H₇ 140 4.2  CH(CH₃)CH₂CH₃ 162 4.3  CH(CH₂CH₃)₂ 178 4.4  C(CH₃)₃ 150 4.5  CH₂CH(CH₃)₂ 125 4.6  CH₂C(CH₃)₃ 160 4.7  C(CH₃)CH(CH₃)₂ 114 4.8  CH(CH₃)CH₂CH(CH₃)₂ 112 4.9  C(CH₃) (C₂H₅)₂ 112 4.10 cyclopropyl 4.11 cyclopentyl 140 4.12 cyclohexyl 154 4.13 cyclopropylmethyl 125 4.14 3-oxetanyl 175 4.15 3-thietanyl 4.16 CH(CH₃)CH═CH₂ 145 4.17 CH₂(CH₃)CH₂ 78 4.18 C(CH₃)₂CH═CH₂ 102 4.19 CH₂C≡CH 94 4.20 CH(CH₃)C≡CH 134 4.21 C(CH₃)₂C≡CH oil 4.22 (CH₂)₂CF₃ 85 4.23 (CH₂)₂Cl 82 4.24 CH(CH₂Cl)₂ 145 4.25 CH₂CF₃ 115 4.26 CH₂CCl₃ 200 4.27 (CH₂)₂SCH₃ 54 4.28 CH(CH₃)CH₂SCH₃ 4.29 (CH₂)₃Cl 95 4.30 CH(CH₃)CH₂C1 142 4.31 CH₂CH═C(CH₃)₂ 98 4.32 C₆H₅ 180 4.33 CH₂C₆H₅ 87 4.34 CH(CH₃)C₆H₅ 118 4.35 CH(CH₃)CN 68 4.36 CH(CH₃)CO₂CH₃ 115-120 4.37 CH(CH₃)CONH₂ 180 4.38 3-tetrahydrofuranyl 105-110 4.39 CH(CH₃)(CF₃) 135 4.40 CH(CF₃)₂ 148 4.41 N═C(CH₃)₂ 160 4.42 H 165 4.43 2-tetrahydrofuranyl 180

The compounds listed below in table 5 can be prepared analogously to the above mentioned examples: TABLE 5

Example No. R^(a) R² R³ m.p. [° C.] 5.1 CH(CH₃)₂ CH₂SCH₃ (CH₂)₄CH₃  96 5.2 CH(CH₃)₂ CH₂OCH₃ CH₂CH₃  80 5.3 CH(CH₃)₂ C₂H₅ nC₃H₇ 118-120 5.4 CH(CH₃)₂ CH₂CH(CH₃)₂ C₂H₅ 143-145 5.5 CH(CH₃)₂ C₂H₅ CH₂CH₂CH(CH₃)₂ 83-84 5.6 CH(CH₃)₂ nC₃H₇ nC₃H₇ 140 5.7 CH(CH₃)₂ CH₂CH═CH₂ C₂H₅ 108 5.8 CH(CH₃)₂ CH₂CH≡C(CH₃)₂ C₂H₅ 103-105 5.9 CH(CH₃)₂ CH₂CH═CH₂ CH₂CH═CH₂ 104  5.10 CH(CH₃)₂ CH₂C≡CH C₂H₅ 78-80  5.11 CH(CH₃)₂ CH₂CH═CH₂ CH₂C≡CH  79  5.12 CH(C₂H₅)₂ CH₃ CH₃ 108

The compounds listed below in table 6 can be prepared analogous to one of the aforementioned processes: TABLE 6

Example m.p. No. R^(b) R^(c) R² R³ [° C.] 6.1 H H C₂H₅ C₂H₅ 125 6.2 H CH₃ C₂H₅ C₂H₅ 146 6.3 H C₂H₅ C₂H₅ C₂H₅ 104-106 6.4 H nC₃H₇ C₂H₅ C₂H₅ 110 6.5 H CH(CH₃)₂ C₂H₅ C₂H₅ 164 6.6 H CH₂CH(CH₃)₂ C₂H₅ C₂H₅ 139 6.7 H CH(CH₃)C₂H₅ C₂H₅ C₂H₅ 6.8 H tC₄H₉ C₂H₅ C₂H₅ 88 6.9 H CH₂CH═CH₂ C₂H₅ C₂H₅ 90 6.10 H C(CH₃)₂CH═CH₂ C₂H₅ C₂H₅ 50 6.11 H CH(CH₃)CH₂OH C₂H₅ C₂H₅ 6.12 H CH(CH₃)CH₂OCH₃ C₂H₅ C₂H₅ 100 6.13 H CH(CH₃)CH₂OC₂H₅ C₂H₅ C₂H₅ 47 6.14 H CH(C₂H₅)CH₂OH C₂H₅ C₂H₅ oil 6.15 H CH(C₂H₅)CH₂OCH₃ C₂H₅ C₂H₅ 118 6.16 H CH(C₂H₅)CH₂OC₂H₅ C₂H₅ C₂H₅ 6.17 H CH(CH₂OH)₂ C₂H₅ C₂H₅ 6.18 H CH(CH₃)CH(OCH₃)₂ C₂H₅ C₂H₅ 6.19 H 3-tetrahydro- C₂H₅ C₂H₅ 79 furanyl 6.20 H (2,2-dimethyl-1, C₂H₅ C₂H₅ 3-dioxan)-5-yl 6.21 CH₃ CH₃ C₂H₅ C₂H₅ 132 6.22 CH₃ C₂H₅ C₂H₅ C₂H₅ 6.23 CH₃ nC₃H₇ C₂H₅ C₂H₅ 6.24 C₂H₅ C₂H₅ C₂H₅ 93 6.25 —(CH₂)₄— C₂H₅ C₂H₅ 73 6.26 —(CH₂)₄— C₂H₅ nC₄H₉ oil 6.27 —(CH₂)₅— C₂H₅ C₂H₅ 6.28 —(CH₂)₆— C₂H₅ C₂H₅ 125 6.29 H C₂H₅ C₂H₅ C₂H₅ 124 6.30 H CH(C₂H₅)₂ C₂H₅ C₂H₅ 165 6.31 H CH(CH₃)CH(OH)CH₃ C₂H₅ C₂H₅ 154 6.32 H CH(CH₃)CH(OCH₃)₂ C₂H₅ C₂H₅ 71 6.33 H (S)—CH(CH₃)C₂H₅ C₂H₅ C₂H₅ 142 6.34 H (R)—CH(CH₃)C₂H₅ C₂H₅ C₂H₅ 142

The compounds listed below in table 7 can be prepared analogous to one of the aforementioned processes: TABLE 7

Example No. R^(d) R² R³ m.p. [ ° C.] 7.1. C₂H₅ C₂H₅ C₂H₅ 7.2. nC₃H₇ C₂H₅ C₂H₅ 7.3. CH(CH₃)₂ C₂H₅ C₂H₅ 115 Biological Application

The α-cyanoacrylates of the formula I and their agriculturally useful salts are suitable for use as herbicides. The herbicidal compositions comprising compounds of the formula I control vegetation on non-crop areas very efficiently, especially at high rates of application. They act against broad-leaved weeds and grass weeds in crops such as wheat, rice, maize, soya and cotton without causing any significant damage to the crop plants. This effect is mainly observed at low rates of application.

Depending on the application method, the compounds in question of the formula I, or herbicidal compositions comprising them, can additionally be employed in a further number of crop plants for eliminating undesirable plants. Examples of suitable crops are the following:

Allium cepa, Ananas comosus, Arachis hypogaea, Asparagus officinalis, Beta vulgaris spec. altissima, Beta vulgaris spec. rapa, Brassica napus var. napus, Brassica napus var. napobrassica, Brassica rapa var. silvestris, Camellia sinensis, Carthamus tinctorius, Carya illinoinensis, Citrus limon, Citrus sinensis, Coffea arabica (Coffea canephora, Coffea liberica), Cucumis sativus, Cynodon dactylon, Daucus carota, Elaeis guineensis, Fragaria vesca, Glycine max, Gossypium hirsutum, (Gossypium arboreum, Gossypium herbaceum, Gossypium vitifolium), Helianthus annuus, Hevea brasiliensis, Hordeum vulgare, Humulus lupulus, Ipomoea batatas, Juglans regia, Lens culinaris, Linum usitatissimum, Lycopersicon lycopersicum, Malus spec., Manihot esculenta, Medicago sativa, Musa spec., Nicotiana tabacum (N.rustica), Olea europaea, Oryza sativa, Phaseolus lunatus, Phaseolus vulgaris, Picea abies, Pinus spec., Pisum sativum, Prunus avium, Prunus persica, Pyrus communis, Ribes sylvestre, Ricinus communis, Saccharum officinarum, Secale cereale, Solanum tuberosum, Sorghum bicolor (s. vulgare), Theobroma cacao, Trifolium pratense, Triticum aestivum, Triticum durum, Vicia faba, Vitis vinifera and Zea mays.

In addition, the compounds of the formula I may also be used in crops which tolerate the action of herbicides owing to breeding, including genetic engineering methods.

The compounds of the formula I, or the compositions comprising them, can be used for example in the form of ready-to-spray aqueous solutions, powders, suspensions, also highly-concentrated aqueous, oily or other suspensions or dispersions, emulsions, oil dispersions, pastes, dusts, materials for spreading, or granules, by means of spraying, atomizing, dusting, spreading or pouring. The use forms depend on the intended aims; in any case, they should ensure the finest possible distribution of the active compounds according to the invention.

The herbicidal compositions comprise a herbicidally effective amount of at least one compound of the formula I or an agriculturally useful salt of I and auxiliaries customarily used for formulative crop protection results.

Suitable inert auxiliaries are essentially:

-   -   mineral oil fractions of medium to high boiling point, such as         kerosene and diesel oil, furthermore coal tar oils and oils of         vegetable or animal origin, aliphatic, cyclic and aromatic         hydrocarbons, e.g. paraffins, tetrahydronaphthalene, alkylated         naphthalenes and their derivatives, alkylated benzenes and their         derivatives, alcohols such as methanol, ethanol, propanol,         butanol and cyclohexanol, ketones such as cyclohexanone,         strongly polar solvents, e.g. amines such as         N-methylpyrrolidone, and water.

Aqueous use forms can be prepared from emulsion concentrates, suspensions, pastes, wettable powders or water-dispersible granules by adding water. To prepare emulsions, pastes or oil dispersions, the substances, either as such or dissolved in an oil or solvent, can be homogenized in water by means of a wetting agent, tackifier, dispersant or emulsifier. Alternatively, it is possible to prepare concentrates comprising active compound, wetting agent, tackifier, dispersant or emulsifier and, if desired, solvent or oil, which are suitable for dilution with water.

Suitable surfactants (adjuvants) are the alkali metal salts, alkaline earth metal salts and ammonium salts of aromatic sulfonic acids, e.g. ligno-, phenol-, naphthalene- and dibutylnaphthalenesulfonic acid, and of fatty acids, alkyl- and alkylarylsulfonates, alkyl sulfates, lauryl ether sulfates and fatty alcohol sulfates, and salts of sulfated hexa-, hepta- and octadecanols, and also of fatty alcohol glycol ethers, condensates of sulfonated naphthalene and its derivatives with formaldehyde, condensates of naphthalene, or of the naphthalenesulfonic acids with phenol and formaldehyde, polyoxyethylene octylphenol ether, ethoxylated isooctyl-, octyl- or nonylphenol, alkylphenyl or tributylphenyl polyglycol ether, alkylaryl polyether alcohols, isotridecyl alcohol fatty alcohol/ethylene oxide condensates, ethoxylated castor oil, polyoxyethylene alkyl ethers or polyoxypropylene alkyl ethers, lauryl alcohol polyglycol ether acetate, sorbitol esters, lignin-sulfite waste liquors or methylcellulose.

Powders, materials for spreading and dusts can be prepared by mixing or grinding the active compounds together with a solid carrier.

Granules, e.g. coated granules, impregnated granules and homogeneous granules, can be prepared by binding the active compounds to solid carriers. Solid carriers are mineral earths, such as silicas, silica gels, silicates, talc, kaolin, limestone, lime, chalk, bole, loess, clay, dolomite, diatomaceous earth, calcium sulfate, magnesium sulfate, magnesium oxide, ground synthetic materials, fertilizers such as ammonium sulfate, ammonium phosphate, ammonium nitrate, ureas, and products of vegetable origin, such as cereal meal, tree bark meal, wood meal and nutshell meal, cellulose powders, or other solid carriers.

The concentrations of the active compounds I in the ready-to-use preparations can be varied within wide ranges. In general, the formulations comprise approximately from 0.001 to 98% by weight, preferably 0.01 to 95% by weight of at least one active compound. The active compounds I are employed in a purity of from 90% to 100%, preferably 95% to 100% (according to NMR spectrum).

The formulation examples which follow illustrate the preparation of such products:

-   -   I. 20 parts by weight of example 4.1 are dissolved in a mixture         composed of 80 parts by weight of alkylated benzene, 10 parts by         weight of the adduct of 8 to 10 mol of ethylene oxide to 1 mol         of oleic acid N-monoethanolamide, 5 parts by weight of calcium         dodecylbenzenesulfonate and 5 parts by weight of the adduct of         40 mol of ethylene oxide to 1 mol of castor oil. Pouring the         solution into 100,000 parts by weight of water and finely         distributing it therein gives an aqueous dispersion which         comprises 0.02% by weight of the active compound.     -   II. 20 parts by weight of example 4.13 are dissolved in a         mixture composed of 40 parts by weight of cyclohexanone, 30         parts by weight of isobutanol, 20 parts by weight of the adduct         of 7 mol of ethylene oxide to 1 mol of isooctylphenol and 10         parts by weight of the adduct of 40 mol of ethylene oxide to 1         mol of castor oil. Pouring the solution into 100,000 parts by         weight of water and finely distributing it therein gives an         aqueous dispersion which comprises 0.02% by weight of the active         compound.     -   III. 20 parts by weight of example 5.7 are dissolved in a         mixture composed of 25 parts by weight of cyclohexanone, 65         parts by weight of a mineral oil fraction of boiling point 210         to 280° C. and 10 parts by weight of the adduct of 40 mol of         ethylene oxide to 1 mol of castor oil. Pouring the solution into         100,000 parts by weight of water and finely distributing it         therein gives an aqueous dispersion which comprises 0.02% by         weight of the active compound.     -   IV. 20 parts by weight of example 4.16 are mixed thoroughly with         3 parts by weight of sodium diisobutylnaphthalene-α-sulfonate,         17 parts by weight of the sodium salt of a lignosulfonic acid         from a sulfite waste liquor and 60 parts by weight of         pulverulent silica gel, and the mixture is ground in a hammer         mill. Finely distributing the mixture in 20,000 parts by weight         of water gives a spray mixture which comprises 0.1% by weight of         the active compound.     -   V. 3 parts by weight of an active compound of example 4.30 are         mixed with 97 parts by weight of finely divided kaolin. This         gives a dust which comprises 3% by weight of active compound.     -   VI. 20 parts by weight of an active compound of example 4.2 are         mixed intimately with 2 parts by weight of calcium         dodecylbenzenesulfonate, 8 parts by weight of fatty alcohol         polyglycol ether, 2 parts by weight of the sodium salt of a         phenol/urea/formaldehyde condensate and 68 parts by weight of a         paraffinic mineral oil. This gives a stable oily dispersion.     -   VII. 1 part by weight of an active compound of example 5.2 is         dissolved in a mixture composed of 70 parts by weight of         cyclohexanone, 20 parts by weight of ethoxylated isooctylphenol         and 10 parts by weight of ethoxylated castor oil. The mixture         can then be diluted with water to the desired concentration of         active compound. This gives a stable emulsion concentrate.     -   VIII. 1 part by weight of an active compound of example 4.25 is         dissolved in a mixture composed of 80 parts by weight of         cyclohexanone and 20 parts by weight of Wettol® EM 31 (=nonionic         emulsifier based on ethoxylated castor oil from BASF). The         mixture can then be diluted with water to the desired         concentration of active compound. This gives a stable emulsion         concentrate.

The compounds of the formula I or the herbicidal compositions can be applied pre- or post-emergence. If the active compounds are less well tolerated by certain crop plants, application techniques may be used in which the herbicidal compositions are sprayed, with the aid of the spraying equipment, in such a way that they come into as little contact as possible, if any, with the leaves of the sensitive crop plants, while the active compounds reach the leaves of undesirable plants growing underneath, or the bare soil surface (post-directed, lay-by).

The rates of application of the compound of the formula I are from 0.001 to 3.0, preferably 0.01 to 1.0, kg/ha of active substance (a.s.), depending on the control target, the season, the target plants and the growth stage.

To widen the spectrum of action and to achieve synergistic effects, the α-cyanoacrylates of the formula I may be mixed with a large number of representatives of other herbicidal or growth-regulating active compounds and then applied concomitantly. Suitable components for mixtures are, for example, 1,2,4-thiadiazoles, 1,3,4-thiadiazoles, amides, aminophosphoric acid and its derivatives, aminotriazoles, anilides, aryl/hetaryl-oxyalkanoic acids and their derivatives, benzoic acid and its derivatives, benzothiadiazinones, 2-(hetaroyl/aroyl)-1,3-cyclohexanediones, hetaryl aryl ketones, benzyl-isoxazolidinones, meta-CF₃-phenyl derivatives, carbamates, quinolinecarboxylic acid and its derivates, chloroacetanilides, cyclohexane-1,3-dione derivatives, diazines, dichloropropionic acid and its derivatives, dihydrobenzofurans, dihydrofuran-3-ones, dinitroanilines, dinitrophenols, diphenyl ethers, dipyridyls, halocarboxylic acids and their derivatives, ureas, 3-phenyluracils, imidazoles, imidazolinones, N-phenyl-3,4,5,6-tetrahydrophthalimides, oxadiazoles, oxiranes, phenols, aryloxy- and hetaryloxyphenoxypropionic esters, phenylacetic acid and its derivatives, 2-phenylpropionic acid and its derivatives, pyrazoles, phenylpyrazoles, pyridazines, pyridinecarboxylic acid and its derivatives, pyrimidyl ethers, sulfonamides, sulfonylureas, triazines, triazinones, triazolinones, triazolecarboxamides and uracils.

It may furthermore be advantageous to apply the compounds I, alone or in combination with other herbicides, in the form of a mixture with other crop protection agents, for example together with agents for controlling pests or phytopathogenic fungi or bacteria. Also of interest is the miscibility with mineral salt solutions, which are employed for treating nutritional and trace element deficiencies. Non-phytotoxic oils and oil concentrates may also be added.

USE EXAMPLES

The herbicidal activity of the α-cyanoacrylates of the formula I was demonstrated by the following greenhouse experiment:

The cultivation containers used were plastic flowerpots containing lomy sand with approximately 3.0% of humus as the substrate. The seeds of the test plants were sown separately for each species.

For the pre-emergence treatment, directly after sowing the active compounds, which had been suspended or emulsified in water, were applied by means of finely distributing nozzles. The containers were irrigated gently to promote germination and growth and subsequently covered with transparent plastic hoods until the plant had rooted. This cover caused uniform germination of the test plants, unless this was adversely affected by reactive compounds. The application rate for a pre-emergence treatment was 0.5 or 1.0 kg of a.s. (active substance)/ha.

For the post-emergence treatment, the test plants were first grown to a height of from 3 to 15 cm, depending on the plant habit, and only then treated with the active compounds which had been suspended or emulsified in water. The test plants were for this purpose either sown directly and grown in the same containers, or they were first grown separately as seedlings and transplanted into the test containers a few days prior to treatment. The application rate for the post-emergence treatment was 0.5 or 1.0 kg of a.s. (active substance)/ha.

Depending on the species, the plants were kept at 10-25° C. or 20-35° C. The test period extended over 2 to 4 weeks. During this time, the plants were tended, and their response to the individual treatments was evaluated.

Evaluation was carried out using a scale from 0 to 100. 100 means no emergence of the plants, or complete destruction of at least the above-ground parts, and 0 means no damage, or normal course of growth.

The plants used in the greenhouse experiments were of the following species: Scientific name Common name Amaranthus retroflexus pig weed Digitaria sanguinalis hairy fingergrass Pharbitis purpurea common morningglory Setaria faberii giant foxtail

The effect of example 4.1, applied by the pre-emergence method at application rates of 1.0 kg/ha, on the harmful plants Amaranthus retroflexus and Setaria faberii was very good.

At an application rate of 1.0 kg/ha, example 4.1 has shown very good post-emergence activity against the undesirable plants Pharbitis purpurea and Setaria faberii.

At an application rate of 1.0 kg/ha at pre-emergence conditions the effect on harmful plants Digitaria sanguinalis and Sateria faberii of examples 4.5, 4.13, 4.16, 4.20, 4.30 and 5.7 was very good.

The effect of example 4.4, 4.6, 4.11, 4.14, 4.23, 4.25, 5.2, 5.3, 5.10 and 6.3 applied under the some conditions on the harmful plant Setaria faberii was very good.

Examples 4.7, 4.29 and 4.35 has shown a good effect under the some conditions against Setaria faberii.

At an application rate of 0.5 kg/ha at pre-emergence conditions the effect on harmful plants Digitaria sanguinalis and Sateria faberii of examples 4.2, 4.19, and 4.22 was very good.

The effect of example 4.17 applied under the some conditions on the harmful plant Digitaria sanguinalis was very good and applied on Setaria faberii was very good.

At an application rate of 1.0 kg/ha at post-emergence conditions the effect of examples 4.4, 4.5, 4.6, 4.11, 4.20, 4.23, 4.29, 5.2, 5.6, 5.7, 5.9, 5.11, 6.3 and 7.3 was very good against undesirable plant Pharbitis purpurea. Example 4.7 has shown under the some conditions a good activity against Pharbitis purpurea.

Example 4.2 has shown a very good post-emergence actirity against Pharbitis purpurea at an application rate of 0.5 kg/ha. 

1. An α-cyanoacrylate of the formula I

where: R¹ is OR^(a) wherein R^(a) is hydrogen, C₁-C₆-alkyl which is partially or fully halogenated and/or carries a substituent from the group consisting of hydroxy, cyano, C₃-C₆-cycloalkyl, three- to six-membered heterocyclyl, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio, C₁-C₆-haloalkylthio, C₁-C₆-alkylsulfinyl, C₁-C₆-haloalkylsulfinyl, C₁-C₆-alkylsulfonyl, C₁-C₆-haloalkylsulfonyl, (C₁-C₄)alkoxycarbonyl, aminocarbonyl, (C₁-C₆)alkylaminocarbonyl, di(C₁-C₆)alkylaminocarbonyl; is branched C₃-C₆-alkyl, branched C₄-C₆-alkenyl, C₃-C₆-alkynyl, C₃-C₆-cycloalkyl, four- to six-membered heterocyclyl, aryl, phenyl(C₁-C₄)alkyl or (C₁-C₆)alkylimino; is NR^(b)R^(c) wherein R^(b) is hydrogen, C₁-C₆-alkyl which may be partially or fully halogenated and/or may carry a substituent from the group consisting of hydroxy, cyano, C₁-C₆-alkoxy, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio, C₁-C₆-halogenalkylthio, C₁-C₆-alkylsulfinyl, C₁-C₆-halogenalkylsulfinyl, C₁-C₆-alkylsulfonyl and C₁-C₆-halogenalkylsulfonyl; is C₂-C₆-alkenyl, C₂-C₆-alkynyl; R^(c) is hydrogen, C₁-C₆-alkyl which may be partially or fully halogenated and/or may carry a substituent from the group consisting of hydroxy, cyano, C₃-C₆-cycloalkyl, three- to six-membered heterocyclyl, C₁-C₆-alkoxy, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio, C₁-C₆-haloalkylthio, C₁-C₆-alkylsulfinyl, C₁-C₆-haloalkylsulfinyl, C₁-C₆-alkylsulfonyl, C₁-C₆-haloalkylsulfonyl, (C₁-C₄)alkoxycarbonyl, aminocarbonyl, (C₁-C₆)alkylaminocarbonyl, di(C₁-C₆)alkylaminocarbonyl; is C₃-C₆-alkenyl, C₃-C₆-alkynyl, C₃-C₆-cycloalkyl, four-to-six-membered heterocyclyl,aryl, phenyl(C₁-C₄-)alkyl or (C₁-C₆)alkylimino; or R^(b) and R^(c) together from a 1,4-butanediyl-, 1,5-pentanediyl- or 1,6-hexanediyl-chain, wherein each of the chains may carry one or more C₁-C₆-alkylgroups; or is SR^(d) wherein R^(d) has the some meaning as R^(c); R² is C₁-C₆-alkyl which may be partially or fully halogenated and/or may carry a substituent from the group consisting of cyano, C₁-C₆-alkoxy, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio, C₁-C₆-haloalkylthio, C₁-C₆-alkylsulfinyl, C₁-C₆-haloalkylsulfinyl, C₁-C₆-alkylsulfonyl and C₁-C₆-haloalkylsulfonyl; is C₂-C₆-alkenyl or C₂-C₆-alkynyl; R³ is C₂-C₆-alkyl or C₁-C₆-alkyl which is partially or fully halogenated and/or carries a substituent from the group consisting of cyano, C₁-C₆-alkoxy, C₁-C₆-haloalkoxy, C₁-C₆-alkylthio, C₁-C₆-haloalkylthio, C₁-C₆-alkylsulfinyl, C₁-C₆-haloalkylsulfinyl, C₁-C₆-alkylsulfonyl and C₁-C₆-haloalkylsulfonyl; is C₂-C₆-alkenyl or C₂-C₆-alkynyl; R⁴ is hydrogen, halogen, cyano or C₁-C₆-alkyl, and its agriculturally useful salts.
 2. An α-cyanoacrylate of formula I as claimed in claim 1 wherein R¹ is OR^(a).
 3. An α-cyanoacrylate of formula I as claimed in claims 1 or 2 wherein R¹ is OR^(a) and R^(a) is branched C₃-C₆-alkyl.
 4. An α-cyanoacrylate of formula I as claimed in claims 1 to 3 wherein R¹ is OR^(a) and R² is C₁-C₆-alkyl.
 5. An α-cyanoacrylate of formula I as claimed in claims 1 to 4 wherein R¹ is OR^(a) and R³ is C₂-C₆-alkyl.
 6. An α-cyanoacrylate of formula I as claimed in claims 1 to 5 wherein R¹ is OR^(a) and R⁴ is hydrogen.
 7. An α-cyanoacrylate of formula I as claimed in claims 1 to 6 wherein R¹ is OR^(a), wherein R^(a) is branched C₃-C₆-alkyl; R² is C₁-C₄-alkyl; R³ is C₂-C₄-alkyl; and R⁴ is hydrogen.
 8. A process for preparing α-cyanoacrylates of formula I as claimed in claims 1 to 7, which comprises reacting an enol ether of formula II

where R¹, R², R³ and R⁴ are as defined under claims 1 to 7 and R⁵ is C₁-C₆-alkyl or benzyl with ammonia.
 9. A process for preparing α-cyanoacrylates of formula I as claimed in claims 1 to 7, which comprises reacting an enol ester of formula VI

where R¹, R², R³ and R⁴ are as defined under claims 1 to 7 and R⁶ is C₁-C₆-alkyl, phenyl or benzyl with ammonia.
 10. A process for preparing α-cyanoacrylates of formula I as claimed in claims 1 to 7, which comprises reacting an imido ester of formula VIII

where R², R³ and R⁴ are as defined under claims 1 to 7 and R⁷ is an C₁-C₆-alkyl radical with a cyanoacetic ester of formula IV

where R¹ is as defined under claims 1 to
 7. 11. A process for preparing α-cyanoacrylates of the formula I as claimed in claims 1 to 7, which comprises reacting an amidine of the formula IX

where R², R³ and R⁴ are as defined under claims 1 to 7 with a cyanoacetic ester of formula IV, where R¹ is as defined under claims 1 to
 7. 12. A process for preparing α-cyonoacrylates of formula I as claimed in claims 1 to 7, which comprises reaching an enaminonitril of formula X

where R², R³ and R⁴ are as defined under claims 1 to 7, with phosgene or equivalents, and subsequent reacting with a compound of formula XII, optionally in presence of a base, HR¹   XII, where R¹ is as defined under claims 1 to
 7. 13. Enol ether of formula II

wherein R¹ to R⁴ are as defined under claims 1 to 7 and R⁵ is C₁-C₆-alkyl or benzyl.
 14. Enol esters of formula VI

wherein R¹ to R⁴ are as defined under claims 1 to 7 and R⁶ is C₁-C₆-alkyl, phenyl or benzyl.
 15. A composition, comprising a herbicidally effective amount of at least one α-cyanoacrylate of formula I or an agriculturally useful salt of I as claimed in any of claims 1 to 7 and auxiliaries customary for formulating crop protection agents.
 16. A process for preparing compositions as claimed in claim 15, which comprises mixing a herbicidally effective amount of at least one α-cyanoacrylate of formula I as claimed in any of claims 1 to 7 or an agriculturally useful salt of I and auxiliaries customary for formulating crop protection agents.
 17. A method for controlling undesirable vegetation, which comprises allowing a herbicidally effective amount of at least one α-cyanoacrylate of formula I as claimed in any of claims 1 to 7 or an agriculturally useful salt of I to act on plants, their habitat and/or seeds.
 18. The use of the α-cyanoacrylates of formula I as claimed in any of claims 1 to 7 or of an agriculturally useful salt of I as herbicides. 